WorldWideScience

Sample records for groundwater systems-a review

  1. Groundwater.

    Science.gov (United States)

    Braids, Olin C.; Gillies, Nola P.

    1978-01-01

    Presents a literature review of groundwater quality covering publications of 1977. This review includes: (1) sources of groundwater contamination; and (2) management of groundwater. A list of 59 references is also presented. (HM)

  2. Review of Groundwater Protection and Management in China

    Institute of Scientific and Technical Information of China (English)

    LIU Dan; ZHANG Ai-ping

    2008-01-01

    This review begins with an introduction of groundwater resources in China and their distribution characteristic, followed by an elaboration of the exploitation and utilization of groundwater and the negative environmental effects from groundwater overexploitation, and a description of the existing groundwater protection and management measures. At last, the existing problems in groundwater protection and management, with some suggestions, are presented.

  3. Natural radioactivity in groundwater--a review.

    Science.gov (United States)

    Dinh Chau, Nguyen; Dulinski, Marek; Jodlowski, Pawel; Nowak, Jakub; Rozanski, Kazimierz; Sleziak, Monika; Wachniew, Przemyslaw

    2011-12-01

    The issue of natural radioactivity in groundwater is reviewed, with emphasis on those radioisotopes which contribute in a significant way to the overall effective dose received by members of the public due to the intake of drinking water originating from groundwater systems. The term 'natural radioactivity' is used in this context to cover all radioactivity present in the environment, including man-made (anthropogenic) radioactivity. Comprehensive discussion of radiological aspects of the presence of natural radionuclides in groundwater, including an overview of current regulations dealing with radioactivity in drinking water, is provided. The presented data indicate that thorough assessments of the committed doses resulting from the presence of natural radioactivity in groundwater are needed, particularly when such water is envisaged for regular intake by infants. They should be based on a precise determination of radioactivity concentration levels of the whole suite of radionuclides, including characterisation of their temporal variability. Equally important is a realistic assessment of water intake values for specific age groups. Only such an evaluation may provide the basis for possible remedial actions.

  4. Using Cl/Br ratios and other indicators to assess potential impacts on groundwater quality from septic systems: A review and examples from principal aquifers in the United States

    Science.gov (United States)

    Katz, B.G.; Eberts, S.M.; Kauffman, L.J.

    2011-01-01

    A detailed review was made of chemical indicators used to identify impacts from septic tanks on groundwater quality. Potential impacts from septic tank leachate on groundwater quality were assessed using the mass ratio of chloride-bromide (Cl/Br), concentrations of selected chemical constituents, and ancillary information (land use, census data, well depth, soil characteristics) for wells in principal aquifers of the United States. Chemical data were evaluated from 1848 domestic wells in 19 aquifers, 121 public-supply wells in 6 aquifers, and associated monitoring wells in four aquifers and their overlying hydrogeologic units. Based on previously reported Cl/Br ratios, statistical comparisons between targeted wells (where Cl/Br ratios range from 400 to 1100 and Cl concentrations range from 20 to 100 mg/L) and non-targeted wells indicated that shallow targeted monitoring and domestic wells (0.5. mg/L) shallow groundwater from target domestic wells, relative to non-target wells (1.5. mg/L), corresponded to significantly higher potassium, boron, chloride, dissolved organic carbon, and sulfate concentrations, which may also indicate the influence of septic-tank effluent. Impacts on groundwater quality from septic systems were most evident for the Eastern Glacial Deposits aquifer and the Northern High Plains aquifer that were associated with the number of housing units using septic tanks, high permeability of overlying sediments, mostly oxic conditions, and shallow wells. Overall, little or no influence from septic systems were found for water samples from the deeper public-supply wells.The Cl/Br ratio is a useful first-level screening tool for assessing possible septic tank influence in water from shallow wells (indicators). ?? 2010.

  5. Using Cl/Br ratios and other indicators to assess potential impacts on groundwater quality from septic systems: A review and examples from principal aquifers in the United States

    Science.gov (United States)

    Katz, Brian G.; Eberts, Sandra M.; Kauffman, Leon J.

    2011-02-01

    SummaryA detailed review was made of chemical indicators used to identify impacts from septic tanks on groundwater quality. Potential impacts from septic tank leachate on groundwater quality were assessed using the mass ratio of chloride-bromide (Cl/Br), concentrations of selected chemical constituents, and ancillary information (land use, census data, well depth, soil characteristics) for wells in principal aquifers of the United States. Chemical data were evaluated from 1848 domestic wells in 19 aquifers, 121 public-supply wells in 6 aquifers, and associated monitoring wells in four aquifers and their overlying hydrogeologic units. Based on previously reported Cl/Br ratios, statistical comparisons between targeted wells (where Cl/Br ratios range from 400 to 1100 and Cl concentrations range from 20 to 100 mg/L) and non-targeted wells indicated that shallow targeted monitoring and domestic wells (0.5 mg/L) shallow groundwater from target domestic wells, relative to non-target wells (1.5 mg/L), corresponded to significantly higher potassium, boron, chloride, dissolved organic carbon, and sulfate concentrations, which may also indicate the influence of septic-tank effluent. Impacts on groundwater quality from septic systems were most evident for the Eastern Glacial Deposits aquifer and the Northern High Plains aquifer that were associated with the number of housing units using septic tanks, high permeability of overlying sediments, mostly oxic conditions, and shallow wells. Overall, little or no influence from septic systems were found for water samples from the deeper public-supply wells. The Cl/Br ratio is a useful first-level screening tool for assessing possible septic tank influence in water from shallow wells (<20 m) with the range of 400-1100. The use of this ratio would be enhanced with information on other chloride sources, temporal variability of chloride and bromide concentrations in shallow groundwater, knowledge of septic-system age and maintenance, and

  6. Review: Regional land subsidence accompanying groundwater extraction

    Science.gov (United States)

    Galloway, Devin L.; Burbey, Thomas J.

    2011-01-01

    The extraction of groundwater can generate land subsidence by causing the compaction of susceptible aquifer systems, typically unconsolidated alluvial or basin-fill aquifer systems comprising aquifers and aquitards. Various ground-based and remotely sensed methods are used to measure and map subsidence. Many areas of subsidence caused by groundwater pumping have been identified and monitored, and corrective measures to slow or halt subsidence have been devised. Two principal means are used to mitigate subsidence caused by groundwater withdrawal—reduction of groundwater withdrawal, and artificial recharge. Analysis and simulation of aquifer-system compaction follow from the basic relations between head, stress, compressibility, and groundwater flow and are addressed primarily using two approaches—one based on conventional groundwater flow theory and one based on linear poroelasticity theory. Research and development to improve the assessment and analysis of aquifer-system compaction, the accompanying subsidence and potential ground ruptures are needed in the topic areas of the hydromechanical behavior of aquitards, the role of horizontal deformation, the application of differential synthetic aperture radar interferometry, and the regional-scale simulation of coupled groundwater flow and aquifer-system deformation to support resource management and hazard mitigation measures.

  7. Groundwater and climate change in Africa : review of recharge studies

    OpenAIRE

    Bonsor, H. C.; MacDonald, A. M.

    2010-01-01

    The review of recharge studies was conducted as part of a one year DFID-funded research programme, aimed at improving understanding of the impacts of climate change on groundwater resources and local livelihoods – see http://www.bgs.ac.uk/GWResilience/. The review is one of a series of components within the project. The overall outputs of the project are: Two hydrogeological case studies in West and East Africa – which assess the storage and availability of groundwater in different aquifers a...

  8. Review: Optimization methods for groundwater modeling and management

    Science.gov (United States)

    Yeh, William W.-G.

    2015-09-01

    Optimization methods have been used in groundwater modeling as well as for the planning and management of groundwater systems. This paper reviews and evaluates the various optimization methods that have been used for solving the inverse problem of parameter identification (estimation), experimental design, and groundwater planning and management. Various model selection criteria are discussed, as well as criteria used for model discrimination. The inverse problem of parameter identification concerns the optimal determination of model parameters using water-level observations. In general, the optimal experimental design seeks to find sampling strategies for the purpose of estimating the unknown model parameters. A typical objective of optimal conjunctive-use planning of surface water and groundwater is to minimize the operational costs of meeting water demand. The optimization methods include mathematical programming techniques such as linear programming, quadratic programming, dynamic programming, stochastic programming, nonlinear programming, and the global search algorithms such as genetic algorithms, simulated annealing, and tabu search. Emphasis is placed on groundwater flow problems as opposed to contaminant transport problems. A typical two-dimensional groundwater flow problem is used to explain the basic formulations and algorithms that have been used to solve the formulated optimization problems.

  9. Review of emerging organic pollutants in groundwater in Slovenia

    Directory of Open Access Journals (Sweden)

    Anja Koroša

    2012-12-01

    Full Text Available Emerging organic compounds EOC are substances which have been only recently determined as pollutants,and substances which have been newly developed or discovered in the environment. EOC in groundwater cancause adverse effects on the environment and human health. They enter into the natural environment as a resultof various anthropogenic activities. The article provides an overview of emerging organic pollutants that occur ingroundwater. These compounds are drug residues, substances originating from personal care products, pesticides,veterinary products, food additives, nanomaterials, industrial and other compounds found in wastewater. Thearticle describes the main sources and the presence of EOC in groundwater, pathways and potential impacts(risks. An overview of EOC detection research in the world is presented. Within the review of Slovenian studiesthe investigations dealing with the determination of wide spectrum of EOC presence in groundwater, with drugresidues in groundwater and waste water, or with the development of analytical methods for these substanceswere analyzed. From the entire analysis we inferred that we must be aware of the possible presence of EOC riskin groundwatereven in small concentrations. To reduce the yet extent unknown risks, it is necessary to determineEOC threshold values in groundwater and their impact. In the future it will be necessary to identify new pollutants,to develop new analytical methods to determine their sources and routes, and in particular, to establishmonitoring for these substances.

  10. Review of risk from potential emerging contaminants in UK groundwater.

    Science.gov (United States)

    Stuart, Marianne; Lapworth, Dan; Crane, Emily; Hart, Alwyn

    2012-02-01

    This paper provides a review of the types of emerging organic groundwater contaminants (EGCs) which are beginning to be found in the UK. EGCs are compounds being found in groundwater that were previously not detectable or known to be significant and can come from agricultural, urban and rural point sources. EGCs include nanomaterials, pesticides, pharmaceuticals, industrial compounds, personal care products, fragrances, water treatment by-products, flame retardants and surfactants, as well as caffeine and nicotine. Many are relatively small polar molecules which may not be effectively removed by drinking water treatment. Data from the UK Environment Agency's groundwater screening programme for organic pollutants found within the 30 most frequently detected compounds a number of EGCs such as pesticide metabolites, caffeine and DEET. Specific determinands frequently detected include pesticides metabolites, pharmaceuticals including carbamazepine and triclosan, nicotine, food additives and alkyl phosphates. This paper discusses the routes by which these compounds enter groundwater, their toxicity and potential risks to drinking water and the environment. It identifies challenges that need to be met to minimise risk to drinking water and ecosystems. Copyright © 2012. Published by Elsevier B.V.

  11. Review: Occurrence of the pathogenic amoeba Naegleria fowleri in groundwater

    Science.gov (United States)

    Bright, Kelly R.; Gerba, Charles P.

    2017-06-01

    Naegleria fowleri is a thermophilic free-living amoeba found worldwide in soils and warm freshwater. It is the causative agent of primary amebic meningoencephalitis, a nearly always fatal disease afflicting mainly children and young adults. Humans are exposed to the organism via swimming, bathing, or other recreational activity during which water is forcefully inhaled into the upper nasal passages. Although many studies have looked at the occurrence of N. fowleri in surface waters, limited information is available regarding its occurrence in groundwater and geothermally heated natural waters such as hot springs. This paper reviews the current literature related to the occurrence of N. fowleri in these waters and the methods employed for its detection. Case reports of potential groundwater exposures are also included. Despite increased interest in N. fowleri in recent years due to well-publicized cases linked to drinking water, many questions still remain unanswered. For instance, why the organism persists in some water sources and not in others is not well understood. The role of biofilms in groundwater wells and plumbing in individual buildings, and the potential for warming due to climate change to expand the occurrence of the organism into new regions, are still unclear. Additional research is needed to address these questions in order to better understand the ecology of N. fowleri and the conditions that result in greater risks to bathers.

  12. Review: Epidemiological evidence of groundwater contribution to global enteric disease, 1948-2015

    Science.gov (United States)

    Murphy, Heather M.; Prioleau, Morgan D.; Borchardt, Mark A.; Hynds, Paul D.

    2017-06-01

    Globally, approximately 2.2 billion people rely on groundwater for daily consumption. It is widely accepted that groundwater is more pristine than surface water but while this assumption is frequently the case, groundwater is not ubiquitously free of contaminants; accordingly, this presumption can result in an unfounded and potentially hazardous sense of security among owners, operators and users. The current paper presents a review of published literature providing epidemiological evidence of the contribution of groundwater to global human enteric infection. An emphasis is placed on enteric pathogens transmitted via the faecal-oral route, and specifically those associated with acute gastrointestinal illness (AGI). The review identified 649 published groundwater outbreaks globally between 1948 and 2013 and several epidemiological studies that show there is an increased risk of AGI associated with the consumption of untreated groundwater. The review identified that the following five pathogens were responsible for most outbreaks: norovirus, Campylobacter, Shigella, Hepatitis A and Giardia. Crudely, the authors estimate that between 35.2 and 59.4 million cases of AGI per year globally could be attributable to the consumption of groundwater. Although groundwater is frequently presumed to be a microbiologically safe source of water for consumption, this review demonstrates that consumers served by an untreated groundwater supply remain at risk to enteric disease. The authors conclude that collaboration between microbiologists, hydrogeologists and epidemiologists is needed to better understand pathogen occurrence, persistence, detection and transport in groundwater as well as build stronger epidemiological evidence documenting the true magnitude of disease associated with groundwater globally.

  13. Groundwater and enteric disease: A review of the epidemiological evidence

    Science.gov (United States)

    Globally, approximately 2.2 billion people rely on groundwater for daily consumption. It is widely accepted that groundwater typically represents a more pristine source of water for human consumption than surface water resources. While this assumption is frequently the case, groundwater is not ubiqu...

  14. FCC riser quick separation system: a review

    Directory of Open Access Journals (Sweden)

    Zhi Li

    2016-10-01

    Full Text Available Abstract The riser reactor is the key unit in the fluid catalytic cracking (FCC process. As the FCC feedstocks become heavier, the product mixture of oil, gas and catalysts must be separated immediately at the outlet of the riser to avoid excessive coking. The quick separation system is the core equipment in the FCC unit. China University of Petroleum (Beijing has developed many kinds of separation system including the fender-stripping cyclone and circulating-stripping cyclone systems, which can increase the separation efficiency and reduce the pressure drop remarkably. For the inner riser system, a vortex quick separation system has been developed. It contains a vortex quick separator and an isolated shell. In order to reduce the separation time, a new type of separator called the short residence time separator system was developed. It can further reduce the separation time to less than 1 s. In this paper, the corresponding design principles, structure and industrial application of these different kinds of separation systems are reviewed. A system that can simultaneously realize quick oil gas separation, quick oil gas extraction and quick pre-stripping of catalysts at the end of the riser is the trend in the future.

  15. Grey water treatment systems: A review

    NARCIS (Netherlands)

    Abu-Ghunmi, L.N.A.H.; Zeeman, G.; Fayyad, M.; Lier, van J.B.

    2011-01-01

    This review aims to discern a treatment for grey water by examining grey water characteristics, reuse standards, technology performance and costs. The review reveals that the systems for treating grey water, whatever its quality, should consist of processes that are able to trap pollutants with a sm

  16. Review of present groundwater monitoring programs at the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Hershey, R.L.; Gillespie, D.

    1993-09-01

    Groundwater monitoring at the Nevada Test Site (NTS) is conducted to detect the presence of radionuclides produced by underground nuclear testing and to verify the quality and safety of groundwater supplies as required by the State of Nevada and federal regulations, and by U.S. Department of Energy (DOE) Orders. Groundwater is monitored at water-supply wells and at other boreholes and wells not specifically designed or located for traditional groundwater monitoring objectives. Different groundwater monitoring programs at the NTS are conducted by several DOE Nevada Operations Office (DOE/NV) contractors. Presently, these individual groundwater monitoring programs have not been assessed or administered under a comprehensive planning approach. Redundancy exists among the programs in both the sampling locations and the constituents analyzed. Also, sampling for certain radionuclides is conducted more frequently than required. The purpose of this report is to review the existing NTS groundwater monitoring programs and make recommendations for modifying the programs so a coordinated, streamlined, and comprehensive monitoring effort may be achieved by DOE/NV. This review will be accomplished in several steps. These include: summarizing the present knowledge of the hydrogeology of the NTS and the potential radionuclide source areas for groundwater contamination; reviewing the existing groundwater monitoring programs at the NTS; examining the rationale for monitoring and the constituents analyzed; reviewing the analytical methods used to quantify tritium activity; discussing monitoring network design criteria; and synthesizing the information presented and making recommendations based on the synthesis. This scope of work was requested by the DOE/NV Hydrologic Resources Management Program (HRMP) and satisfies the 1993 (fiscal year) HRMP Groundwater Monitoring Program Review task.

  17. Occurrence of nitrate in Tanzanian groundwater aquifers: A review

    Science.gov (United States)

    Elisante, Eliapenda; Muzuka, Alfred N. N.

    2017-03-01

    More than 25 % of Tanzanian depends on groundwater as the main source of water for drinking, irrigation and industrial activities. The current trend of land use may lead to groundwater contamination and thus increasing risks associated with the usage of contaminated water. Nitrate is one of the contaminants resulting largely from anthropogenic activities that may find its way to the aquifers and thus threatening the quality of groundwater. Elevated levels of nitrate in groundwater may lead to human health and environmental problems. The current trend of land use in Tanzania associated with high population growth, poor sanitation facilities and fertilizer usage may lead to nitrate contamination of groundwater. This paper therefore aimed at providing an overview of to what extent human activities have altered the concentration of nitrate in groundwater aquifers in Tanzania. The concentration of nitrate in Tanzanian groundwater is variable with highest values observable in Dar es Salaam (up to 477.6 mg/l), Dodoma (up to 441.1 mg/l), Tanga (above 100 mg/l) and Manyara (180 mg/l). Such high values can be attributed to various human activities including onsite sanitation in urban centres and agricultural activities in rural areas. Furthermore, there are some signs of increasing concentration of nitrate in groundwater with time in some areas in response to increased human activities. However, reports on levels and trends of nitrate in groundwater in many regions of the country are lacking. For Tanzania to appropriately address the issue of groundwater contamination, a deliberate move to determine nitrate concentration in groundwater is required, as well as protection of recharge basins and improvement of onsite sanitation systems.

  18. Occurrence of nitrate in Tanzanian groundwater aquifers: A review

    Science.gov (United States)

    Elisante, Eliapenda; Muzuka, Alfred N. N.

    2015-03-01

    More than 25 % of Tanzanian depends on groundwater as the main source of water for drinking, irrigation and industrial activities. The current trend of land use may lead to groundwater contamination and thus increasing risks associated with the usage of contaminated water. Nitrate is one of the contaminants resulting largely from anthropogenic activities that may find its way to the aquifers and thus threatening the quality of groundwater. Elevated levels of nitrate in groundwater may lead to human health and environmental problems. The current trend of land use in Tanzania associated with high population growth, poor sanitation facilities and fertilizer usage may lead to nitrate contamination of groundwater. This paper therefore aimed at providing an overview of to what extent human activities have altered the concentration of nitrate in groundwater aquifers in Tanzania. The concentration of nitrate in Tanzanian groundwater is variable with highest values observable in Dar es Salaam (up to 477.6 mg/l), Dodoma (up to 441.1 mg/l), Tanga (above 100 mg/l) and Manyara (180 mg/l). Such high values can be attributed to various human activities including onsite sanitation in urban centres and agricultural activities in rural areas. Furthermore, there are some signs of increasing concentration of nitrate in groundwater with time in some areas in response to increased human activities. However, reports on levels and trends of nitrate in groundwater in many regions of the country are lacking. For Tanzania to appropriately address the issue of groundwater contamination, a deliberate move to determine nitrate concentration in groundwater is required, as well as protection of recharge basins and improvement of onsite sanitation systems.

  19. The Maryland Coastal Plain Aquifer Information System: A GIS-based tool for assessing groundwater resources

    Science.gov (United States)

    Andreasen, David C.; Nardi, Mark R.; Staley, Andrew W.; Achmad, Grufron; Grace, John W.

    2016-01-01

    Groundwater is the source of drinking water for ∼1.4 million people in the Coastal Plain Province of Maryland (USA). In addition, groundwater is essential for commercial, industrial, and agricultural uses. Approximately 0.757 × 109 L d–1 (200 million gallons/d) were withdrawn in 2010. As a result of decades of withdrawals from the coastal plain confined aquifers, groundwater levels have declined by as much as 70 m (230 ft) from estimated prepumping levels. Other issues posing challenges to long-term groundwater sustainability include degraded water quality from both man-made and natural sources, reduced stream base flow, land subsidence, and changing recharge patterns (drought) caused by climate change. In Maryland, groundwater supply is managed primarily by the Maryland Department of the Environment, which seeks to balance reasonable use of the resource with long-term sustainability. The chief goal of groundwater management in Maryland is to ensure safe and adequate supplies for all current and future users through the implementation of appropriate usage, planning, and conservation policies. To assist in that effort, the geographic information system (GIS)–based Maryland Coastal Plain Aquifer Information System was developed as a tool to help water managers access and visualize groundwater data for use in the evaluation of groundwater allocation and use permits. The system, contained within an ESRI ArcMap desktop environment, includes both interpreted and basic data for 16 aquifers and 14 confining units. Data map layers include aquifer and ­confining unit layer surfaces, aquifer extents, borehole information, hydraulic properties, time-series groundwater-level data, well records, and geophysical and lithologic logs. The aquifer and confining unit layer surfaces were generated specifically for the GIS system. The system also contains select groundwater-quality data and map layers that quantify groundwater and surface-water withdrawals. The aquifer

  20. Effects of climate change on coastal groundwater systems: A modeling study in the Netherlands

    NARCIS (Netherlands)

    Oude Essink, Gualbert; Van Baaren, Esther S.; De Louw, Perry G.B.

    2010-01-01

    Climate change in combination with increased anthropogenic activities will affect coastal groundwater systems throughout the world. In this paper, we focus on a coastal groundwater system that is already threatened by a relatively high seawater level: the low‐lying Dutch Delta. Nearly one third of

  1. [Effects of reclaimed water recharge on groundwater quality: a review].

    Science.gov (United States)

    Chen, Wei-Ping; Lü, Si-Dan; Wang, Mei-E; Jiao, Wen-Tao

    2013-05-01

    Reclaimed water recharge to groundwater is an effective way to relieve water resource crisis. However, reclaimed water contains some pollutants such as nitrate, heavy metals, and new type contaminants, and thus, there exists definite environmental risk in the reclaimed water recharge to groundwater. To promote the development of reclaimed water recharge to groundwater and the safe use of reclaimed water in China, this paper analyzed the relevant literatures and practical experiences around the world, and summarized the effects of different reclaimed water recharge modes on the groundwater quality. Surface recharge makes the salt and nitrate contents in groundwater increased but the risk of heavy metals pollution be smaller, whereas well recharge can induce the arsenic release from sedimentary aquifers, which needs to be paid more attention to. New type contaminants are the hotspots in current researches, and their real risks are unknown. Pathogens have less pollution risks on groundwater, but some virus with strong activity can have the risks. Some suggestions were put forward to reduce the risks associated with the reclaimed water recharge to groundwater in China.

  2. Review of Electrical and Gravity Methods of Near-Surface Exploration for Groundwater

    Directory of Open Access Journals (Sweden)

    W. O. Raji

    2014-12-01

    Full Text Available The theory and practice of electrical and gravity methods of geophysics for groundwater exploration was reviewed with illustrations and data examples. With the goal of reducing cases of borehole/water-well failure attributed to the lack of the knowledge of the methods of geophysics for groundwater exploration and development, the paper reviews the basic concepts, field procedures for data acquisition, data processing, and interpretation as applied to the subject matter. Given a case study of groundwater exploration in University of Ilorin Campus, the three important techniques of electrical method of groundwater exploration are explained and illustrated using field data obtained in a previous study. Interpretation of resistivity data shows that an area measuring low resistivity (high conductivity, having thick pile of unconsolidated rock, and underlained by fracture crystalline is a ‘bright spot’ for citing borehole for groundwater abstraction in a basement complex area. Further to this, gravity method of groundwater exploration was discussed with field data from Wokbedilo community in Ethopia. Bouguer and reduced gravity anomaly results were presented as maps and contours to demonstrate how gravity data can be inverted to map groundwater aquifers and subsurface geological structures during groundwater exploration.

  3. [Groundwater].

    Science.gov (United States)

    González De Posada, Francisco

    2012-01-01

    From the perspective of Hydrogeology, the concept and an introductory general typology of groundwater are established. From the perspective of Geotechnical Engineering works, the physical and mathematical equations of the hydraulics of permeable materials, which are implemented, by electric analogical simulation, to two unique cases of global importance, are considered: the bailing during the construction of the dry dock of the "new shipyard of the Bahia de Cádiz" and the waterproofing of the "Hatillo dam" in the Dominican Republic. From a physical fundamental perspective, the theories which are the subset of "analogical physical theories of Fourier type transport" are related, among which the one constituted by the laws of Adolf Fick in physiology occupies a historic role of some relevance. And finally, as a philosophical abstraction of so much useful mathematical process, the one which is called "the Galilean principle of the mathematical design of the Nature" is dealt with.

  4. Local food systems: a sustainability review

    OpenAIRE

    Kwong, Edwin

    2011-01-01

    The evolution of global food systems has led to industrial food production processes that have environmental and social external costs. Consumer awareness about sustainability issues brings a heightened awareness of general consumption impacts in our food choices. This paper explores sustainability factors within local food systems in order to understand the impact on sustainability issues within the local food economy. A review of environmental, economic, and social issues within a sustai...

  5. WIND ENERGY CONVERSION SYSTEMS - A TECHNICAL REVIEW

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    N. RAMESH BABU

    2013-08-01

    Full Text Available Wind power production has been under the main focus for the past decade in power production and tremendous amount of research work is going on renewable energy, specifically on wind power extraction. Wind power provides an eco-friendly power generation and helps to meet the national energy demand when there is a diminishing trend in terms of non-renewable resources. This paper reviews the modeling of Wind Energy Conversion Systems (WECS, control strategies of controllers and various Maximum Power Point Tracking (MPPT technologies that are being proposed for efficient production of wind energy from the available resource.

  6. NIOSOMES AS NANOCARRIER SYSTEMS: A REVIEW

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    Badari Srikanth Reddy, Jakkani Surya Chandra Padman and Voruganti Santosh*

    2012-06-01

    Full Text Available Nonionic surfactant vesicles (niosomes result from the organized assembly of sufficiently insoluble surfactants in aqueous media. The low cost of ingredients and manufacture, possibility of large-scale production, stability and the resultant ease of storage of niosomes have led to the exploitation of these nano carriers as alternatives to other micro and nano-encapsulation technologies. Niosomes are an already established encapsulation technology in different areas including food, biotechnology, cosmetics and pharmaceutics. This article reviews general properties of niosomes along with recent trends in their preparation methods and their applications in the encapsulation and delivery of bioactive agents via different routes.

  7. Microfluidic enzymatic biosensing systems: A review.

    Science.gov (United States)

    Mross, Stefan; Pierrat, Sebastien; Zimmermann, Tom; Kraft, Michael

    2015-08-15

    Microfluidic biosensing systems with enzyme-based detection have been extensively studied in the last years owing to features such as high specificity, a broad range of analytes and a high degree of automation. This review gives an overview of the most important factors associated with these systems. In the first part, frequently used immobilization protocols such as physisorption and covalent bonding and detection techniques such as amperometry and fluorescence measurements are discussed with respect to effort, lifetime and measurement range. The Michaelis-Menten model describing the kinetics of enzymatic reactions, the role of redox mediators and the limitations of the linear measurement range of enzymatic sensors are introduced. Several possibilities of extending the linear measurement range in microfluidic systems such as diffusion-limiting membranes and the flow injection setup are presented. Regarding the integration of enzymes into microfluidic systems during the fabrication process, the constraints imposed by the biomolecules due to the limited usage of high temperatures and solvents are addressed. In the second part, the most common forms of enzyme integration into microfluidic systems, i.e. in channels and on electrodes, on microparticles, on paper and thread and as injected enzyme solutions, are reviewed, focusing on fabrication, applications and performance.

  8. Continuous Glucose Monitoring Systems: A Review

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    Sandeep Kumar Vashist

    2013-10-01

    Full Text Available There have been continuous advances in the field of glucose monitoring during the last four decades, which have led to the development of highly evolved blood glucose meters, non-invasive glucose monitoring (NGM devices and continuous glucose monitoring systems (CGMS. Glucose monitoring is an integral part of diabetes management, and the maintenance of physiological blood glucose concentration is the only way for a diabetic to avoid life-threatening diabetic complications. CGMS have led to tremendous improvements in diabetic management, as shown by the significant lowering of glycated hemoglobin (HbA1c in adults with type I diabetes. Most of the CGMS have been minimally-invasive, although the more recent ones are based on NGM techniques. This manuscript reviews the advances in CGMS for diabetes management along with the future prospects and the challenges involved.

  9. Foot Plantar Pressure Measurement System: A Review

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    Yufridin Wahab

    2012-07-01

    Full Text Available Foot plantar pressure is the pressure field that acts between the foot and the support surface during everyday locomotor activities. Information derived from such pressure measures is important in gait and posture research for diagnosing lower limb problems, footwear design, sport biomechanics, injury prevention and other applications. This paper reviews foot plantar sensors characteristics as reported in the literature in addition to foot plantar pressure measurement systems applied to a variety of research problems. Strengths and limitations of current systems are discussed and a wireless foot plantar pressure system is proposed suitable for measuring high pressure distributions under the foot with high accuracy and reliability. The novel system is based on highly linear pressure sensors with no hysteresis.

  10. Kannada Character Recognition System A Review

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    Indira, K

    2010-01-01

    Intensive research has been done on optical character recognition ocr and a large number of articles have been published on this topic during the last few decades. Many commercial OCR systems are now available in the market, but most of these systems work for Roman, Chinese, Japanese and Arabic characters. There are no sufficient number of works on Indian language character recognition especially Kannada script among 12 major scripts in India. This paper presents a review of existing work on printed Kannada script and their results. The characteristics of Kannada script and Kannada Character Recognition System kcr are discussed in detail. Finally fusion at the classifier level is proposed to increase the recognition accuracy.

  11. Abortion in Iranian legal system: a review.

    Directory of Open Access Journals (Sweden)

    Mahmoud Abbasi

    2014-02-01

    Full Text Available Abortion traditionally means, "to miscarry" and is still known as a problem which societies has been trying to reduce its rate by using legal means. Despite the pregnant women and fetuses have being historically supported; abortion was firstly criminalized in 1926 in Iran, 20 years after establishment of modern legal system. During next 53 years this situation changed dramatically, so in 1979, the time of Islamic Revolution, aborting fetuses before 12 weeks and therapeutic abortion (TA during all the pregnancy length was legitimate, based on regulations that used medical justification. After 1979 the situation changed into a totally conservative and restrictive approach and new Islamic concepts as "Blood Money" and "Ensoulment" entered the legal debates around abortion. During the next 33 years, again a trend of decriminalization for the act of abortion has been continuing. Reduction of punishments and omitting retaliation for criminal abortions, recognizing fetal and maternal medical indications including some immunologic problems as legitimate reasons for aborting fetuses before 4 months and omitting the fathers' consent as a necessary condition for TA are among these changes. The start point for this decriminalization process was public and professional need, which was responded by religious government, firstly by issuing juristic rulings (Fatwas as a non-official way, followed by ratification of "Therapeutic Abortion Act" (TAA and other regulations as an official pathway. Here, we have reviewed this trend of decriminalization, the role of public and professional request in initiating such process and the rule-based language of TAA.

  12. Ontology Supported Information Systems: A Review

    Directory of Open Access Journals (Sweden)

    Padmavathi, T.

    2014-12-01

    Full Text Available The exponential growth of information on the web far exceeds the capacity of present day information retrieval systems and search engines, making information integration on the web difficult. In order to overcome this, semantic web technologies were proposed by the World Wide Web Consortium (W3C to achieve a higher degree of automation and precision in information retrieval systems. Semantic web, with its promise to deliver machine understanding to the traditional web, has attracted a significant amount of research from academia as well as from industries. Semantic web is an extension of the current web in which data can be shared and reused across the internet. RDF and ontology are two essential components of the semantic web architecture which support a common framework for data storage and representation of data semantics, respectively. Ontologies being the backbone of semantic web applications, it is more relevant to study various approaches in their application, usage, and integration into web services. In this article, an effort has been made to review the research work being undertaken in the area of design and development of ontology supported information systems. This paper also briefly explains the emerging semantic web technologies and standards.

  13. Heart monitoring systems--a review.

    Science.gov (United States)

    Jain, Puneet Kumar; Tiwari, Anil Kumar

    2014-11-01

    To diagnose health status of the heart, heart monitoring systems use heart signals produced during each cardiac cycle. Many types of signals are acquired to analyze heart functionality and hence several heart monitoring systems such as phonocardiography, electrocardiography, photoplethysmography and seismocardiography are used in practice. Recently, focus on the at-home monitoring of the heart is increasing for long term monitoring, which minimizes risks associated with the patients diagnosed with cardiovascular diseases. It leads to increasing research interest in portable systems having features such as signal transmission capability, unobtrusiveness, and low power consumption. In this paper we intend to provide a detailed review of recent advancements of such heart monitoring systems. We introduce the heart monitoring system in five modules: (1) body sensors, (2) signal conditioning, (3) analog to digital converter (ADC) and compression, (4) wireless transmission, and (5) analysis and classification. In each module, we provide a brief introduction about the function of the module, recent developments, and their limitation and challenges.

  14. Review on Trickle Irrigation Application in Groundwater Irrigation Schemes

    Directory of Open Access Journals (Sweden)

    Prastowo

    2006-04-01

    Full Text Available The Government of Indonesia has developed groundwater irrigation schemes in some province e.g. East Java, Central Java, Yogyakarta, Wast Java, Bali, West Nusa Tenggara and East Nusa Tenggara. However, not all regions were able to optimally utilize it. The irrigation effeciency of groundwater irrigation scheme was about 59%, while the wells-pumping efficiencies were varied from 28 to 98 %. In thefuture, the irrigation effieciency should be increased to anticipate water deficit during dry season. The application of trickle irrigation in indonesia has not been widely developed. Although trickle system has been used, however, it is still limited for few commercial agribusinesses. Trickle irrigation systems have a prospect to be developed in some regions having limited water resources. For preliminary stage, the systems could be applied in groundwater irrigation schemes that have been developed either by farmers or government.

  15. Review of information on interactions between vegetation and groundwater

    CSIR Research Space (South Africa)

    Le Maitre, David C

    1999-04-01

    Full Text Available Research Commission (WRC), culminating in a report entitled The Interaction between Vegeta- tion and Groundwater: Research Priorities for South Africa (Scott and Le Maitre, 1998). It concentrates on studies of the impacts of vegetation on groundwater.... * To whom all correspondence should be addressed ( (021) 888-2610; fax (021) 888-2693; e-mail dlmaitre@csir.co.za Received 17 August 1998; accepted in revised form 4 December 1998. ISSN 0378-4738 = Water SA Vol. 25 No. 2 April 1999138 Available on website...

  16. Transport of reactive carriers and contaminants in groundwater systems : a dynamic competitive happening

    NARCIS (Netherlands)

    Weerd, van de H.

    2000-01-01

    Transport of contaminants constitutes a potential threat for public health and ecosystems. One of the potential pathways for contaminant transport in groundwater systems is transport adsorbed to carriers (colloidal particles, large molecules). Figure 1 shows a detail of a

  17. Transport of reactive carriers and contaminants in groundwater systems : a dynamic competitive happening

    NARCIS (Netherlands)

    Weerd, van de H.

    2000-01-01

    Transport of contaminants constitutes a potential threat for public health and ecosystems. One of the potential pathways for contaminant transport in groundwater systems is transport adsorbed to carriers (colloidal particles, large molecules). Figure 1 shows a detail of a grou

  18. Occurrence, sources and fate of pharmaceuticals and personal care products in the groundwater: A review

    Directory of Open Access Journals (Sweden)

    Qian Sui

    2015-11-01

    Full Text Available The presence of pharmaceuticals and personal care products (PPCPs in the aquatic environment may pose potential threat to the ecosystem and human health, hence PPCPs have aroused much concern over the world. The contamination of PPCPs in the groundwater, the main source of drinking water supply in many countries and regions, has been extensively studied in the last decade. This paper reviews the occurrence of frequently detected PPCPs, including antibiotics, anti-inflammatories, lipid-regulators, carbamazepine, caffeine, and N,N-diethyl-m-toluamide in groundwater, with special concern to the progress made over the past three years. Possible emission sources for PPCPs in groundwater, such as wastewater and contaminated surface water, landfills, septic systems, livestock breeding and sewer leakage, are summarized. Besides, adsorption, migration and degradation, the dominant mechanisms in the subsurface transport and fate of PPCPs, are discussed, and the insights into the future study of PPCPs in the groundwater are provided.

  19. Groundwater resources management through the applications of simulation modeling: a review.

    Science.gov (United States)

    Singh, Ajay

    2014-11-15

    The global population is increasing rapidly and expected to touch the 9.5 billion mark by 2050 from the current 7.2 billion. The management of the groundwater resources is a challenging task worldwide against the backdrop of the growing water demand for industrial, agricultural, and domestic uses and shrinking resources. Moreover, this task has been hampered significantly due to declining/rising groundwater levels and associated contamination. A broad range of solutions could be considered to address the aforementioned problems of groundwater management, but the effectiveness of all the solutions and their combinations cannot be verified with field experiments. Given their predictive capability, simulation models are often the only viable means of providing input to management decisions, as they can forecast the likely impacts of a particular water management strategy. This paper presents a comprehensive review on the simulation modeling applications for the management of groundwater resources. The past papers on the overview of groundwater simulation models, use of remote sensing and GIS in groundwater modeling, and application of simulation models in arid and semiarid regions are described in detail. Conclusions are drawn where gaps exist and more research needs to be focused. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. Arsenic contamination of groundwater: a review of sources, prevalence, health risks, and strategies for mitigation.

    Science.gov (United States)

    Shankar, Shiv; Shanker, Uma; Shikha

    2014-01-01

    Arsenic contamination of groundwater in different parts of the world is an outcome of natural and/or anthropogenic sources, leading to adverse effects on human health and ecosystem. Millions of people from different countries are heavily dependent on groundwater containing elevated level of As for drinking purposes. As contamination of groundwater, poses a serious risk to human health. Excessive and prolonged exposure of inorganic As with drinking water is causing arsenicosis, a deteriorating and disabling disease characterized by skin lesions and pigmentation of the skin, patches on palm of the hands and soles of the feet. Arsenic poisoning culminates into potentially fatal diseases like skin and internal cancers. This paper reviews sources, speciation, and mobility of As and global overview of groundwater As contamination. The paper also critically reviews the As led human health risks, its uptake, metabolism, and toxicity mechanisms. The paper provides an overview of the state-of-the-art knowledge on the alternative As free drinking water and various technologies (oxidation, coagulation flocculation, adsorption, and microbial) for mitigation of the problem of As contamination of groundwater.

  1. Arsenic Contamination of Groundwater: A Review of Sources, Prevalence, Health Risks, and Strategies for Mitigation

    Directory of Open Access Journals (Sweden)

    Shiv Shankar

    2014-01-01

    Full Text Available Arsenic contamination of groundwater in different parts of the world is an outcome of natural and/or anthropogenic sources, leading to adverse effects on human health and ecosystem. Millions of people from different countries are heavily dependent on groundwater containing elevated level of As for drinking purposes. As contamination of groundwater, poses a serious risk to human health. Excessive and prolonged exposure of inorganic As with drinking water is causing arsenicosis, a deteriorating and disabling disease characterized by skin lesions and pigmentation of the skin, patches on palm of the hands and soles of the feet. Arsenic poisoning culminates into potentially fatal diseases like skin and internal cancers. This paper reviews sources, speciation, and mobility of As and global overview of groundwater As contamination. The paper also critically reviews the As led human health risks, its uptake, metabolism, and toxicity mechanisms. The paper provides an overview of the state-of-the-art knowledge on the alternative As free drinking water and various technologies (oxidation, coagulation flocculation, adsorption, and microbial for mitigation of the problem of As contamination of groundwater.

  2. Arsenic Contamination of Groundwater: A Review of Sources, Prevalence, Health Risks, and Strategies for Mitigation

    Science.gov (United States)

    Shikha

    2014-01-01

    Arsenic contamination of groundwater in different parts of the world is an outcome of natural and/or anthropogenic sources, leading to adverse effects on human health and ecosystem. Millions of people from different countries are heavily dependent on groundwater containing elevated level of As for drinking purposes. As contamination of groundwater, poses a serious risk to human health. Excessive and prolonged exposure of inorganic As with drinking water is causing arsenicosis, a deteriorating and disabling disease characterized by skin lesions and pigmentation of the skin, patches on palm of the hands and soles of the feet. Arsenic poisoning culminates into potentially fatal diseases like skin and internal cancers. This paper reviews sources, speciation, and mobility of As and global overview of groundwater As contamination. The paper also critically reviews the As led human health risks, its uptake, metabolism, and toxicity mechanisms. The paper provides an overview of the state-of-the-art knowledge on the alternative As free drinking water and various technologies (oxidation, coagulation flocculation, adsorption, and microbial) for mitigation of the problem of As contamination of groundwater. PMID:25374935

  3. Geoinformatics Approach for Groundwater Prospects and Quality Studies - A Review

    Directory of Open Access Journals (Sweden)

    Rajvir Singh

    2015-06-01

    Full Text Available Water is a prime requirement for all the living and non-living processes. On the earth, 71% is water but the availability of useable fresh water for drinking and other purposes is about 2.8%. Out of this 2.8 % fresh water, the share of groundwater is only 0.6% that makes it more pertinent to conservation, preservation, and management. The urbanization, industrialization, and intensive agricultural practices have put further pressure on the available fresh water. The modern techniques like space technology, GIS and GPS have great utility in mapping, monitoring, planning and management of water resources. The temporal satellite data in different spectral bands and on different spatial resolutions make the remote sensing satellite data highly useful for mapping and monitoring of an area. The geographical information system (GIS has the capability to store, retrieve, edit and represent the data in informative way. The global positioning system (GPS gives the real time geo-coordinates, path and altitude of desired object or terrain. Thus, the geoinformatics have huge potential for solving the problems of groundwater availability and quality, and there is a need to harness the potential of these techniques for societal benefits to provide water everyone.

  4. Quantitative analysis of saltwater-freshwater relationships in groundwater systems-A historical perspective

    Science.gov (United States)

    Reilly, T.E.; Goodman, A.S.

    1985-01-01

    Although much progress has been made toward the mathematical description of saltwater-freshwater relationships in groundwater systems since the late 19th century, the advective and dispersive mechanisms involved are still incompletely understood. This article documents the major historical advances in this subject and summarizes the major direction of current studies. From the time of Badon Ghyben and Herzberg, it has been recognized that density is important in mathematically describing saltwater-freshwater systems. Other mechanisms, such as hydrodynamic dispersion, were identified later and are still not fully understood. Quantitative analysis of a saltwater-freshwater system attempts to mathematically describe the physical system and the important mechanisms using reasonable simplifications and assumptions. This paper, in developing the history of quantitative analysis discusses many of these simplifications and assumptions and their effect on describing and understanding the phenomenon. ?? 1985.

  5. Groundwater vulnerability to climate change: A review of the assessment methodology.

    Science.gov (United States)

    Aslam, Rana Ammar; Shrestha, Sangam; Pandey, Vishnu Prasad

    2017-09-05

    Impacts of climate change on water resources, especially groundwater, can no longer be hidden. These impacts are further exacerbated under the integrated influence of climate variability, climate change and anthropogenic activities. The degree of impact varies according to geographical location and other factors leading systems and regions towards different levels of vulnerability. In the recent past, several attempts have been made in various regions across the globe to quantify the impacts and consequences of climate and non-climate factors in terms of vulnerability to groundwater resources. Firstly, this paper provides a structured review of the available literature, aiming to critically analyse and highlight the limitations and knowledge gaps involved in vulnerability (of groundwater to climate change) assessment methodologies. The effects of indicator choice and the importance of including composite indicators are then emphasised. A new integrated approach for the assessment of groundwater vulnerability to climate change is proposed to successfully address those limitations. This review concludes that the choice of indicator has a significant role in defining the reliability of computed results. The effect of an individual indicator is also apparent but the consideration of a combination (variety) of indicators may give more realistic results. Therefore, in future, depending upon the local conditions and scale of the study, indicators from various groups should be chosen. Furthermore, there are various assumptions involved in previous methodologies, which limit their scope by introducing uncertainty in the calculated results. These limitations can be overcome by implementing the proposed approach. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Review: Impact of underground structures on the flow of urban groundwater

    Science.gov (United States)

    Attard, Guillaume; Winiarski, Thierry; Rossier, Yvan; Eisenlohr, Laurent

    2016-02-01

    Property economics favours the vertical development of cities but flow of groundwater can be affected by the use of underground space in them. This review article presents the state of the art regarding the impact of disturbances caused by underground structures (tunnels, basements of buildings, deep foundations, etc.) on the groundwater flow in urban aquifers. The structures built in the underground levels of urban areas are presented and organised in terms of their impact on flow: obstacle to the flow or disturbance of the groundwater budget of the flow system. These two types of disturbance are described in relation to the structure area and the urban area. The work reviewed shows, on one hand, the individual impacts of different urban underground structures, and on the other, their cumulative impacts on flow, using real case studies. Lastly, the works are placed in perspective regarding the integration of underground structures with the aim of operational management of an urban aquifer. The literature presents deterministic numerical modelling as a tool capable of contributing to this aim, in that it helps to quantify the effect of an underground infrastructure project on groundwater flow, which is crucial for decision-making processes. It can also be an operational decision-aid tool for choosing construction techniques or for formulating strategies to manage the water resource.

  7. A review of methods for modelling environmental tracers in groundwater: Advantages of tracer concentration simulation

    Science.gov (United States)

    Turnadge, Chris; Smerdon, Brian D.

    2014-11-01

    Mathematical models of varying complexity have been developed since the 1960s to interpret environmental tracer concentrations in groundwater flow systems. This review examines published studies of model-based environmental tracer interpretation, the progress of different modelling approaches, and also considers the value of modelling tracer concentrations directly rather than estimations of groundwater age. Based on citation metrics generated using the Web of Science and Google Scholar reference databases, the most highly utilised interpretation approaches are lumped parameter models (421 citations), followed closely by direct age models (220 citations). A third approach is the use of mixing cell models (99 citations). Although lumped parameter models are conceptually simple and require limited data, they are unsuitable for characterising the internal dynamics of a hydrogeological system and/or under conditions where large scale anthropogenic stresses occur within a groundwater basin. Groundwater age modelling, and in particular, the simulation of environmental tracer transport that explicitly accounts for the accumulation and decay of tracer mass, has proven to be highly beneficial in constraining numerical models. Recent improvements in computing power have made numerical simulation of tracer transport feasible. We argue that, unlike directly simulated ages, the results of tracer mass transport simulation can be compared directly to observations, without needing to correct for apparent age bias or other confounding factors.

  8. A review of groundwater recharge estimation in humid and semi-arid African regions

    Science.gov (United States)

    Chung, Il-Moon; Kim, Nam Won

    2016-04-01

    For the review of African recharge estimation, the distinct methods such as the geochemical approach, a method using groundwater level data, the streamflow method, and the water balance methods were first outlined. The major challenge of an African recharge study is the lack of basic data. Thus, this work suggests how to deal with this limitation and from future perspective using recently developed technologies such as RS, GIS, etc. With the rapid growth of information technology, more and more data, in terms of both volume and variety, are expected to be made available on the internet in the near future. RS technology has a great potential to revolutionize the groundwater development and management in the future by providing unique and completely new hydrological and hydrogeological data. However, at present, the RS data should be considered along with the conventional field data. In spite of the weaknesses of water balance methods in semi-arid areas, recently developed water balance methods combined with GIS technology are powerful tools for estimating groundwater re-charge, when spatial-temporal variability of components in water balance is taken into account (Lerner et al., 1990; De Vries and Simmers, 2002; Eilers et al., 2007).When enough data sets are available, integrated surface-groundwater modeling is recommended for more accurate estimation of groundwater recharge and discharge. Acknowledgements This work was supported by a grant(14RDRP-B076275-01-000000) from Infrastructure and transportation technology promotion research Program funded by the Ministry of Land, Infrastructure and Transport of Korean government.

  9. Review: Selenium contamination, fate, and reactive transport in groundwater in relation to human health

    Science.gov (United States)

    Bailey, Ryan T.

    2016-12-01

    Selenium (Se) is an essential micro-nutrient for humans, but can be toxic at high levels of intake. Se deficiency and Se toxicity are linked with serious diseases, with some regions worldwide experiencing Se deficiency due to Se-poor rocks and soils and other areas dealing with Se toxicity due to the presence of Se-enriched geologic materials. In addition, Se is consumed primarily through plants that take up Se from soil and through animal products that consume these plants. Hence, the soil and groundwater system play important roles in determining the effect of Se on human health. This paper reviews current understanding of Se fate and transport in soil and groundwater systems and its relation to human health, with a focus on alluvial systems, soil systems, and the interface between alluvial systems and Cretaceous shale that release Se via oxidation processes. The review focuses first on the relation between Se and human health, followed by a summary of Se distribution in soil-aquifer systems, with an emphasis on the quantitative relationship between Se content in soil and Se concentration in underlying groundwater. The physical, chemical, and microbial processes that govern Se fate and transport in subsurface systems then are presented, followed by numerical modeling techniques used to simulate these processes in study regions and available remediation strategies for either Se-deficient or Se-toxic regions. This paper can serve as a guide to any field, laboratory or modeling study aimed at assessing Se fate and transport in groundwater systems and its relation to human health.

  10. Review: Selenium contamination, fate, and reactive transport in groundwater in relation to human health

    Science.gov (United States)

    Bailey, Ryan T.

    2017-06-01

    Selenium (Se) is an essential micro-nutrient for humans, but can be toxic at high levels of intake. Se deficiency and Se toxicity are linked with serious diseases, with some regions worldwide experiencing Se deficiency due to Se-poor rocks and soils and other areas dealing with Se toxicity due to the presence of Se-enriched geologic materials. In addition, Se is consumed primarily through plants that take up Se from soil and through animal products that consume these plants. Hence, the soil and groundwater system play important roles in determining the effect of Se on human health. This paper reviews current understanding of Se fate and transport in soil and groundwater systems and its relation to human health, with a focus on alluvial systems, soil systems, and the interface between alluvial systems and Cretaceous shale that release Se via oxidation processes. The review focuses first on the relation between Se and human health, followed by a summary of Se distribution in soil-aquifer systems, with an emphasis on the quantitative relationship between Se content in soil and Se concentration in underlying groundwater. The physical, chemical, and microbial processes that govern Se fate and transport in subsurface systems then are presented, followed by numerical modeling techniques used to simulate these processes in study regions and available remediation strategies for either Se-deficient or Se-toxic regions. This paper can serve as a guide to any field, laboratory or modeling study aimed at assessing Se fate and transport in groundwater systems and its relation to human health.

  11. Use of iron-based technologies in contaminated land and groundwater remediation: A review

    Energy Technology Data Exchange (ETDEWEB)

    Cundy, Andrew B. [School of Environment and Technology, University of Brighton, Lewes Road, Brighton BN2 4GJ (United Kingdom)], E-mail: A.Cundy@brighton.ac.uk; Hopkinson, Laurence [School of Environment and Technology, University of Brighton, Lewes Road, Brighton BN2 4GJ (United Kingdom); Whitby, Raymond L.D. [School of Pharmacy and Biomolecular Sciences, University of Brighton, Lewes Road, Brighton BN2 4GJ (United Kingdom)

    2008-08-01

    Reactions involving iron play a major role in the environmental cycling of a wide range of important organic, inorganic and radioactive contaminants. Consequently, a range of environmental clean-up technologies have been proposed or developed which utilise iron chemistry to remediate contaminated land and surface and subsurface waters, e.g. the use of injected zero zero-valent iron nanoparticles to remediate organic contaminant plumes; the generation of iron oxyhydroxide-based substrates for arsenic removal from contaminated waters; etc. This paper reviews some of the latest iron-based technologies in contaminated land and groundwater remediation, their current state of development, and their potential applications and limitations.

  12. INDEPENDENT REVIEW OF THE X-701B GROUNDWATER REMEDY, PORTSMOUTH, OHIO: TECHNICAL EVALUATION AND RECOMMENDATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Looney, B.; Eddy-Dilek, C.; Costanza, J.; Rossabi, J.; Early, T.; Skubal, K.; Magnuson, C.

    2008-12-15

    The Department of Energy Portsmouth Paducah Project Office requested assistance from Department of Energy Office of Environmental Management (EM-22) to provide independent technical experts to evaluate past and ongoing remedial activities at the Portsmouth facility that were completed to address TCE contamination associated with the X-701B groundwater plume and to make recommendations for future efforts. The Independent Technical Review team was provided with a detailed and specific charter. The charter requested that the technical team first review the past and current activities completed for the X-701B groundwater remedy for trichloroethene (TCE) in accordance with a Decision Document that was issued by Ohio EPA on December 8, 2003 and a Work Plan that was approved by Ohio EPA on September 22, 2006. The remedy for X-701B divides the activities into four phases: Phase I - Initial Source Area Treatment, Phase II - Expanded Source Area Treatment, Phase III - Evaluation and Reporting, and Phase IV - Downgradient Remediation and Confirmation of Source Area Treatment. Phase I of the remedy was completed during FY2006, and DOE has now completed six oxidant injection events within Phase II. The Independent Technical Review team was asked to evaluate Phase II activities, including soil and groundwater results, and to determine whether or not the criteria that were defined in the Work Plan for the Phase II end point had been met. The following criteria are defined in the Work Plan as an acceptable Phase II end point: (1) Groundwater samples from the identified source area monitoring wells have concentrations below the Preliminary Remediation Goal (PRG) for TCE in groundwater, or (2) The remedy is no longer effective in removing TCE mass from the source area. In addition, the charter specifies that if the Review Team determines that the Phase II endpoint has not been reached, then the team should address the following issues: (1) If additional injection events are

  13. Arsenic in groundwaters in the Northern Appalachian Mountain belt: a review of patterns and processes.

    Science.gov (United States)

    Peters, Stephen C

    2008-07-29

    Naturally occurring arsenic in the bedrock of the Northern Appalachian Mountain belt was first recognized in the late 19th century. The knowledge of the behavior of arsenic in groundwater in this region has lagged behind nearly a century, with the popular press reporting on local studies in the early 1980s, and most peer-reviewed research articles on regional patterns conducted and written in the late 1990s and early 2000s. Research reports have shown that within this high arsenic region, between 6% and 22% of households using private drinking water wells contain arsenic in excess of 10 microg/L, the United States Environmental Protection Agency's maximum contaminant level. In nearly all reports, arsenic in drinking water was derived from naturally occurring geologic sources, typically arsenopyrite, substituted sulfides such as arsenian pyrite, and nanoscale minerals such as westerveldite. In most studies, arsenic concentrations in groundwater were controlled by pH dependent adsorption to mineral surfaces, most commonly iron oxide minerals. In some cases, reductive dissolution of iron minerals has been shown to increase arsenic concentrations in groundwater, more commonly associated with anthropogenic activities such as landfills. Evidence of nitrate reduction promoting the presence of arsenic(V) and iron(III) minerals in anoxic environments has been shown to occur in surface waters, and in this manuscript we show this process perhaps applies to groundwater. The geologic explanation for the high arsenic region in the Northern Appalachian Mountain belt is most likely the crustal recycling of arsenic as an incompatible element during tectonic activity. Accretion of multiple terranes, in particular Avalonia and the Central Maine Terrane of New England appear to be connected to the presence of high concentrations of arsenic. Continued tectonic activity and recycling of these older terranes may also be responsible for the high arsenic observed in the Triassic rift

  14. Patient Safety Learning Systems: A Systematic Review and Qualitative Synthesis

    Science.gov (United States)

    Lambrinos, Anna; Holubowich, Corinne

    2017-01-01

    Background A patient safety learning system (sometimes called a critical incident reporting system) refers to structured reporting, collation, and analysis of critical incidents. To inform a provincial working group's recommendations for an Ontario Patient Safety Event Learning System, a systematic review was undertaken to determine design features that would optimize its adoption into the health care system and would inform implementation strategies. Methods The objective of this review was to address two research questions: (a) what are the barriers to and facilitators of successful adoption of a patient safety learning system reported by health professionals and (b) what design components maximize successful adoption and implementation? To answer the first question, we used a published systematic review. To answer the second question, we used scoping study methodology. Results Common barriers reported in the literature by health care professionals included fear of blame, legal penalties, the perception that incident reporting does not improve patient safety, lack of organizational support, inadequate feedback, lack of knowledge about incident reporting systems, and lack of understanding about what constitutes an error. Common facilitators included a non-accusatory environment, the perception that incident reporting improves safety, clarification of the route of reporting and of how the system uses reports, enhanced feedback, role models (such as managers) using and promoting reporting, legislated protection of those who report, ability to report anonymously, education and training opportunities, and clear guidelines on what to report. Components of a patient safety learning system that increased successful adoption and implementation were emphasis on a blame-free culture that encourages reporting and learning, clear guidelines on how and what to report, making sure the system is user-friendly, organizational development support for data analysis to generate

  15. Current perspectives on post systems: a literature review.

    Science.gov (United States)

    Goracci, C; Ferrari, M

    2011-06-01

    This literature review summarizes the most recent and reliable evidence on post systems. A search was limited to review articles published over the last 10 years in dental journals with an impact factor. Papers cited in the initially retrieved review articles were also included if significant. Preservation of tooth tissue, presence of a ferrule effect, and adhesion are regarded as the most effective conditions for long-term success of post-endodontic restorations. Adhesively luted fibre-reinforced composite post restorations have demonstrated satisfactory survival rates over relatively long follow-up periods. The clinical effectiveness of such restorations has been mainly ascribed to the more biomimetic behaviour of fibre-reinforced composite posts that reduces the risk of vertical root fractures. The most common type of failure when using fibre posts is post debonding and it is generally agreed that achieving stable adhesion to intraradicular dentine is more challenging than to coronal dentine. Several factors related to endodontic treatment, root canal shape, post space preparation, post translucency, adhesive cement handling and curing may have an influence on the outcome of the luting procedure. The most reliable results in fibre post cementation are obtained by etch-and-rinse adhesives in combination with dual-cure resin cements. The use of self-adhesive resin cements has also been proposed. Simplification is an obvious advantage of these new materials. However, the durability of their bond still needs to be verified with long-term clinical studies. Several techniques for pre-treating the fibre-reinforced composite post surface have been tested with the aim of improving the bond strength at the post-core and post-cement interfaces. Silicoating followed by silanization currently appears to be the most effective and convenient method for this purpose. In conclusion, the available evidence validates the use of fibre posts as an alternative to metal posts and

  16. Patient Safety Learning Systems: A Systematic Review and Qualitative Synthesis.

    Science.gov (United States)

    2017-01-01

    A patient safety learning system (sometimes called a critical incident reporting system) refers to structured reporting, collation, and analysis of critical incidents. To inform a provincial working group's recommendations for an Ontario Patient Safety Event Learning System, a systematic review was undertaken to determine design features that would optimize its adoption into the health care system and would inform implementation strategies. The objective of this review was to address two research questions: (a) what are the barriers to and facilitators of successful adoption of a patient safety learning system reported by health professionals and (b) what design components maximize successful adoption and implementation? To answer the first question, we used a published systematic review. To answer the second question, we used scoping study methodology. Common barriers reported in the literature by health care professionals included fear of blame, legal penalties, the perception that incident reporting does not improve patient safety, lack of organizational support, inadequate feedback, lack of knowledge about incident reporting systems, and lack of understanding about what constitutes an error. Common facilitators included a non-accusatory environment, the perception that incident reporting improves safety, clarification of the route of reporting and of how the system uses reports, enhanced feedback, role models (such as managers) using and promoting reporting, legislated protection of those who report, ability to report anonymously, education and training opportunities, and clear guidelines on what to report. Components of a patient safety learning system that increased successful adoption and implementation were emphasis on a blame-free culture that encourages reporting and learning, clear guidelines on how and what to report, making sure the system is user-friendly, organizational development support for data analysis to generate meaningful learning outcomes

  17. Review of the impacts of leaking CO 2 gas and brine on groundwater quality

    Energy Technology Data Exchange (ETDEWEB)

    Qafoku, Nikolla P.; Lawter, Amanda R.; Bacon, Diana H.; Zheng, Liange; Kyle, Jennifer; Brown, Christopher F.

    2017-06-01

    This review paper provides a synthetic view of the existing knowledge and summarizes data and findings of the recent literature on the subject of the potential leaking of CO2 from the deep subsurface storage reservoirs and the effects on aquifer quality. New ideas and concepts are developed and insights are also provided. The objectives of this paper are to: 1) present and discuss potential risks for groundwater degradation due to CO2 gas and brine exposure; 2) identify the set of geochemical data required to assess and predict aquifer responses to CO2 and brine leakage. Specifically, this paper will discuss the following issues: 1) Aquifer responses (such as changes in aqueous phase/groundwater chemical composition; changes in solid phase chemistry and mineralogy; changes in the extent and rate of reactions and processes and possible establishment of a new network of reactions and processes affecting or controlling overall mobility of major, minor, and trace elements; development of conceptual and reduced order models (ROMs) to describe and predict aquifer responses); 2) The degree of impact such as significant or insignificant changes in pH and major, minor, and trace element release that depend on the following controlling variables; the effect of leaking plume characteristics (gas composition, pure CO2 and/or CO2 -CH4 -H2S mixtures and brine concentration and composition (trace metals); aquifer properties [such as initial aqueous phase conditions and mineralogy: minerals controlling sediments’ response (e.g., calcite, Si bearing minerals, etc.)]; overview of relevant hydrogeological and geochemical processes related to the impact of CO2 gas and brine on groundwater quality; the fate of the elements released from sediments or transported with brine (such as precipitation/incorporation into minerals (calcite and other minerals), adsorption, electron transfer reactions, the role of natural attenuation; whether or not the release of metals following exposure to

  18. Independent Technical Review of the X-740 Groundwater Remedy, Portsmouth, Ohio: Technical Evaluation and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Looney, B.; Rhia, B.; Jackson, D.; Eddy-Dilek, C.

    2010-04-30

    Two major remedial campaigns have been applied to a plume of trichloroethene (TCE) contaminated groundwater near the former X-740 facility at the Portsmouth Gaseous Diffusion Plant in Piketon Ohio. The two selected technologies, phytoremediation using a stand of hybrid poplar trees from 1999-2007 and in situ chemical oxidation using modified Fenton's Reagent from 2008-2009, have proven ineffective in achieving remedial action objectives (RAOs). The 'poor' performance of these technologies is a direct result of site specific conditions and the local contaminant hydrogeology. Key among these challenges is the highly heterogeneous subsurface geology with a thin contaminated aquifer zone (the Gallia) - the behavior of the contamination in the Gallia is currently dominated by slow release of TCE from the clay of the overlying Minford formation, from the sandstone of the underlying Berea formation, and from clayey layers within the Gallia itself. In response to the remediation challenges for the X-740 plume, the Portsmouth team (including the US Department of Energy (DOE), the site contractor (CDM), and the Ohio Environmental Protection Agency (OEPA)) is evaluating the feasibility of remediation at this site and identifying specific alternatives that are well matched to site conditions and that would maximize the potential for achieving RAOs. To support this evaluation, the DOE Office of Groundwater and Soil Remediation (EM-32) assembled a team of experts to serve as a resource and provide input and recommendations to Portsmouth. Despite the challenging site conditions and the failure of the previous two remediation campaigns to adequately move the site toward RAOs, the review team was unanimous in the conclusion that an effective combination of cost effective technologies can be identified. Further, the team expressed optimism that RAOs can be achieved if realistic timeframes are accepted by all parties. The initial efforts of the review team focused on

  19. Review: Current and emerging methods for catchment-scale modelling of recharge and evapotranspiration from shallow groundwater

    Science.gov (United States)

    Doble, Rebecca C.; Crosbie, Russell S.

    2016-09-01

    A review is provided of the current and emerging methods for modelling catchment-scale recharge and evapotranspiration (ET) in shallow groundwater systems. With increasing availability of data, such as remotely sensed reflectance and land-surface temperature data, it is now possible to model groundwater recharge and ET with more physically realistic complexity and greater levels of confidence. The conceptual representation of recharge and ET in groundwater models is critical in areas with shallow groundwater. The depth dependence of recharge and vegetation water-use feedback requires additional calibration to fluxes as well as heads. Explicit definition of gross recharge vs. net recharge, and groundwater ET vs. unsaturated zone ET, in preparing model inputs and reporting model results is necessary to avoid double accounting in the water balance. Methods for modelling recharge and ET include (1) use of simple surface boundary conditions for groundwater flow models, (2) coupling saturated groundwater models with one-dimensional unsaturated-zone models, and (3) more complex fully-coupled surface-unsaturated-saturated conceptualisations. Model emulation provides a means for including complex model behaviours with lower computational effort. A precise ET surface input is essential for accurate model outputs, and the model conceptualisation depends on the spatial and temporal scales under investigation. Using remote sensing information for recharge and ET inputs in model calibration or in model-data fusion is an area for future research development. Improved use of uncertainty analysis to provide probability bounds for groundwater model outputs, understanding model sensitivity and parameter dependence, and guidance for further field-data acquisition are also areas for future research.

  20. Dynamic Vulnerability of Karst Systems: a Concept to understand qualitative and quantitative Aspects of Karst springs due to Changes in Groundwater Recharge

    Science.gov (United States)

    Huggenberger, P.; Butscher, C.; Epting, J.; Auckenthaler, A.

    2015-12-01

    Karst groundwater resources represent valuable water resources, which may be affected by different types of pollution and changes of groundwater recharge by climate change. In many parts of Europe, it has been predicted that record-breaking heat waves, such as the one experienced in 2003 and 2015, will become more frequent. At the same time, even as summers become drier, the incidence of severe precipitation events could increase. What is the influence such changes to the quantitative and qualitative aspects of Karst groundwater systems? A factor to be considered in conjunction with groundwater quality is the vulnerability of the resource, which is defined as the sensitivity of a groundwater system to pollution. Intrinsic vulnerability refers to the sensitivity to pollution when considering only natural, geogenic conditions without the effects of human activities such as contaminant release. Intrinsic vulnerability depends on the recharge conditions, which are dependent on the surface and subsurface structure and on precipitation and evaporation patterns. The latter are highly time dependent. Therefore, our groundwater vulnerability concept also includes dynamic aspects of the system, the variations of spatial and temporal components. We present results of combined monitoring and modelling experiments of several types of Karst systems in the Tabular and the Folded Jura of NW Switzerland. The recharge, conduit flow, diffuse flow(RCD) rainfall-discharge model "RCD-seasonal" was used to simulate the discharge and substance concentration of several spring. This lumped parameter model include: the recharge system (soil and epikarst system), the conduit flow system, and the diffuse flow system. The numerically derived Dynamic Vulnerability Index (DVI) can indicate qualitative changes of spring water with sufficient accuracy to be used for drinking water management. In addition, the results obtained from the test sites indicate a decrease in short-lived contaminants in

  1. A Review of Advances in the Identification and Characterization of Groundwater Dependent Ecosystems Using Geospatial Technologies

    Directory of Open Access Journals (Sweden)

    Isabel C. Pérez Hoyos

    2016-03-01

    Full Text Available Groundwater Dependent Ecosystem (GDE protection is increasingly being recognized as essential for the sustainable management and allocation of water resources. GDE services are crucial for human well-being and for a variety of flora and fauna. However, the conservation of GDEs is only possible if knowledge about their location and extent is available. Several studies have focused on the identification of GDEs at specific locations using ground-based measurements. However, recent progress in remote sensing technologies and their integration with Geographic Information Systems (GIS has provided alternative ways to map GDEs at a much larger spatial extent. This paper presents a review of the geospatial methods that have been used to map and delineate GDEs at spatial different extents. Additionally, a summary of the satellite sensors useful for identification of GDEs and the integration of remote sensing data with ground-based measurements in the process of mapping GDEs is presented.

  2. INDEPENDENT REVIEW OF THE X-701B GROUNDWATER REMEDY, PORTSMOUTH, OHIO: TECHNICAL EVALUATION AND RECOMMENDATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Looney, B.; Eddy-Dilek, C.; Costanza, J.; Rossabi, J.; Early, T.; Skubal, K.; Magnuson, C.

    2008-12-15

    The Department of Energy Portsmouth Paducah Project Office requested assistance from Department of Energy Office of Environmental Management (EM-22) to provide independent technical experts to evaluate past and ongoing remedial activities at the Portsmouth facility that were completed to address TCE contamination associated with the X-701B groundwater plume and to make recommendations for future efforts. The Independent Technical Review team was provided with a detailed and specific charter. The charter requested that the technical team first review the past and current activities completed for the X-701B groundwater remedy for trichloroethene (TCE) in accordance with a Decision Document that was issued by Ohio EPA on December 8, 2003 and a Work Plan that was approved by Ohio EPA on September 22, 2006. The remedy for X-701B divides the activities into four phases: Phase I - Initial Source Area Treatment, Phase II - Expanded Source Area Treatment, Phase III - Evaluation and Reporting, and Phase IV - Downgradient Remediation and Confirmation of Source Area Treatment. Phase I of the remedy was completed during FY2006, and DOE has now completed six oxidant injection events within Phase II. The Independent Technical Review team was asked to evaluate Phase II activities, including soil and groundwater results, and to determine whether or not the criteria that were defined in the Work Plan for the Phase II end point had been met. The following criteria are defined in the Work Plan as an acceptable Phase II end point: (1) Groundwater samples from the identified source area monitoring wells have concentrations below the Preliminary Remediation Goal (PRG) for TCE in groundwater, or (2) The remedy is no longer effective in removing TCE mass from the source area. In addition, the charter specifies that if the Review Team determines that the Phase II endpoint has not been reached, then the team should address the following issues: (1) If additional injection events are

  3. Monitoring and Management of Karstic Coastal Groundwater in a Changing Environment (Southern Italy: A Review of a Regional Experience

    Directory of Open Access Journals (Sweden)

    Maurizio Polemio

    2016-04-01

    Full Text Available The population concentration in coastal areas and the increase of groundwater discharge in combination with the peculiarities of karstic coastal aquifers constitute a huge worldwide problem, which is particularly relevant for coastal aquifers of the Mediterranean basin. This paper offers a review of scientific activities realized to pursue the optimal utilization of Apulian coastal groundwater. Apulia, with a coastline extending for over 800 km, is the Italian region with the largest coastal karst aquifers. Apulian aquifers have suffered both in terms of water quality and quantity. Some regional regulations were implemented from the 1970s with the purpose of controlling the number of wells, well locations, and well discharge. The practical effects of these management criteria, the temporal and spatial trend of recharge, groundwater quality, and seawater intrusion effects are discussed based on long-term monitoring. The efficacy of existing management tools and the development of predictive scenarios to identify the best way to reconcile irrigation and demands for high-quality drinking water have been pursued in a selected area. The Salento peninsula was selected as the Apulian aquifer portion exposed to the highest risk of quality degradation due to seawater intrusion. The capability of large-scale numerical models in groundwater management was tested, particularly for achieving forecast scenarios to evaluate the impacts of climate change on groundwater resources. The results show qualitative and quantitative groundwater trends from 1930 to 2060 and emphasize the substantial decrease of the piezometric level and a serious worsening of groundwater salinization due to seawater intrusion.

  4. Phreatophytic vegetation and groundwater fluctuations: a review of current research and application of ecosystem response modeling with an emphasis on great basin vegetation.

    Science.gov (United States)

    Naumburg, Elke; Mata-Gonzalez, Ricardo; Hunter, Rachael G; McLendon, Terry; Martin, David W

    2005-06-01

    Although changes in depth to groundwater occur naturally, anthropogenic alterations may exacerbate these fluctuations and, thus, affect vegetation reliant on groundwater. These effects include changes in physiology, structure, and community dynamics, particularly in arid regions where groundwater can be an important water source for many plants. To properly manage ecosystems subject to changes in depth to groundwater, plant responses to both rising and falling groundwater tables must be understood. However, most research has focused exclusively on riparian ecosystems, ignoring regions where groundwater is available to a wider range of species. Here, we review responses of riparian and other species to changes in groundwater levels in arid environments. Although decreasing water tables often result in plant water stress and reduced live biomass, the converse is not necessarily true for rising water tables. Initially, rising water tables kill flooded roots because most species cannot tolerate the associated low oxygen levels. Thus, flooded plants can also experience water stress. Ultimately, individual species responses to either scenario depend on drought and flooding tolerance and the change in root system size and water uptake capacity. However, additional environmental and biological factors can play important roles in the severity of vegetation response to altered groundwater tables. Using the reviewed information, we created two conceptual models to highlight vegetation dynamics in areas with groundwater fluctuations. These models use flow charts to identify key vegetation and ecosystem properties and their responses to changes in groundwater tables to predict community responses. We then incorporated key concepts from these models into EDYS, a comprehensive ecosystem model, to highlight the potential complexity of predicting community change under different fluctuating groundwater scenarios. Such models provide a valuable tool for managing vegetation and

  5. Control strategies for crane systems: A comprehensive review

    Science.gov (United States)

    Ramli, Liyana; Mohamed, Z.; Abdullahi, Auwalu M.; Jaafar, H. I.; Lazim, Izzuddin M.

    2017-10-01

    Crane systems are tremendously utilised in numerous heavy load transportation industries, and therefore, the control of crane systems is a well-established research field. As the last review paper was published more than a decade ago, there is a lack of collected and organised information regarding the latest and the newest updates on control strategies for crane control systems. Hence, this paper presents a comprehensive review of crane control strategies discussing the latest research works during the years from 2000 to 2016. Various crane types and control issues are highlighted, followed by the main focus of this paper, an extensive review of the control schemes for diverse types of crane systems that have been carried out in the 21st century. A brief review on modelling of single-pendulum and double-pendulum crane systems is also given. In addition, anti-sway control systems for industrial cranes that are available on the market is described. This paper summarises most of the related work and also pays a special focus on research trends regarding the control of crane systems that have been previously published in the literature. It is envisaged that this review paper will be helpful to new researchers when identifying research directions for this particular area of interest.

  6. A Review of Groundwater Arsenic Contamination in Bangladesh: The Millennium Development Goal Era and Beyond

    Directory of Open Access Journals (Sweden)

    Fakir Md. Yunus

    2016-02-01

    Full Text Available Arsenic contamination in drinking water has a detrimental impact on human health which profoundly impairs the quality of life. Despite recognition of the adverse health implications of arsenic toxicity, there have been few studies to date to suggest measures that could be taken to overcome arsenic contamination. After the statement in 2000 WHO Bulletin that Bangladesh has been experiencing the largest mass poisoning of population in history, we researched existing literature to assess the magnitude of groundwater arsenic contamination in Bangladesh. The literature reviewed related research that had been initiated and/or completed since the implementation of the Millennium Development Goals (MDGs under four domains: (1 extent of arsenic contamination; (2 health consequences; (3 mitigation and technologies and (4 future directions. To this means, a review matrix was established for analysis of previous literature based on these four core domains. Our findings revealed that several high-quality research articles were produced at the beginning of the MDG period, but efforts have dwindled in recent years. Furthermore, there were only a few studies conducted that focused on developing suitable solutions for managing arsenic contamination. Although the government of Bangladesh has made its population’s access to safe drinking water a priority agenda item, there are still pockets of the population that continue to suffer from arsenic toxicity due to contaminated water supplies.

  7. A Review of Groundwater Arsenic Contamination in Bangladesh: The Millennium Development Goal Era and Beyond.

    Science.gov (United States)

    Yunus, Fakir Md; Khan, Safayet; Chowdhury, Priyanka; Milton, Abul Hasnat; Hussain, Sumaira; Rahman, Mahfuzar

    2016-02-15

    Arsenic contamination in drinking water has a detrimental impact on human health which profoundly impairs the quality of life. Despite recognition of the adverse health implications of arsenic toxicity, there have been few studies to date to suggest measures that could be taken to overcome arsenic contamination. After the statement in 2000 WHO Bulletin that Bangladesh has been experiencing the largest mass poisoning of population in history, we researched existing literature to assess the magnitude of groundwater arsenic contamination in Bangladesh. The literature reviewed related research that had been initiated and/or completed since the implementation of the Millennium Development Goals (MDGs) under four domains: (1) extent of arsenic contamination; (2) health consequences; (3) mitigation and technologies and (4) future directions. To this means, a review matrix was established for analysis of previous literature based on these four core domains. Our findings revealed that several high-quality research articles were produced at the beginning of the MDG period, but efforts have dwindled in recent years. Furthermore, there were only a few studies conducted that focused on developing suitable solutions for managing arsenic contamination. Although the government of Bangladesh has made its population's access to safe drinking water a priority agenda item, there are still pockets of the population that continue to suffer from arsenic toxicity due to contaminated water supplies.

  8. Understanding waste for lean health information systems: a preliminary review.

    Science.gov (United States)

    Kalong, Nadia Awang; Yusof, Maryati Mohd

    2013-01-01

    Despite the rapid application of the Lean method in healthcare, its study in IT environments, particularly in Health Information Systems (HIS), is still limited primarily by a lack of waste identification. This paper aims to review the literature to provide an insight into the nature of waste in HIS from the perspective of Lean management. Eight waste frameworks within the context of healthcare and information technology were reviewed. Based on the review, it was found that all the seven waste categories from the manufacturing sector also exist in both the healthcare and IT domains. However, the nature of the waste varied depending on the processes of the domains. A number of additional waste categories were also identified. The findings reveal that the traditional waste model can be adapted to identify waste in both the healthcare and IT sectors.

  9. A review of groundwater contamination near municipal solid waste landfill sites in China.

    Science.gov (United States)

    Han, Zhiyong; Ma, Haining; Shi, Guozhong; He, Li; Wei, Luoyu; Shi, Qingqing

    2016-11-01

    Landfills are the most widely used method for municipal solid waste (MSW) disposal method in China. However, these facilities have caused serious groundwater contamination due to the leakage of leachate. This study, analyzed 32 scientific papers, a field survey and an environmental assessment report related to groundwater contamination caused by landfills in China. The groundwater quality in the vicinity of landfills was assessed as "very bad" by a comprehensive score (FI) of 7.85 by the Grading Method in China. Variety of pollutants consisting of 96 groundwater pollutants, 3 organic matter indicators, 2 visual pollutants and 6 aggregative pollutants had been detected in the various studies. Twenty-two kinds of pollutants were considered to be dominant. According to the Kruskal-Wallis test and the median test, groundwater contamination differed significantly between regions in China, but there were no significant differences between dry season and wet season measurements, except for some pollutants in a few landfill sites. Generally, the groundwater contamination appeared in the initial landfill stage after five years and peaked some years afterward. In this stage, the Nemerow Index (PI) of groundwater increased exponentially as landfill age increased at some sites, but afterwards decreased exponentially with increasing age at others. After 25years, the groundwater contamination was very low at selected landfills. The PI values of landfills decreased exponentially as the pollutant migration distance increased. Therefore, the groundwater contamination mainly appeared within 1000m of a landfill and most of serious groundwater contamination occurred within 200m. The results not only indicate that the groundwater contamination near MSW landfills should be a concern, but also are valuable to remediate the groundwater contamination near MSW landfills and to prevent the MSW landfill from secondary pollutions, especially for developing countries considering the similar

  10. Effectiveness of Intelligent Tutoring Systems: A Meta-Analytic Review

    Science.gov (United States)

    Kulik, James A.; Fletcher, J. D.

    2016-01-01

    This review describes a meta-analysis of findings from 50 controlled evaluations of intelligent computer tutoring systems. The median effect of intelligent tutoring in the 50 evaluations was to raise test scores 0.66 standard deviations over conventional levels, or from the 50th to the 75th percentile. However, the amount of improvement found in…

  11. Effectiveness of Intelligent Tutoring Systems: A Meta Analytic Review

    Science.gov (United States)

    2017-02-01

    Michigan J. D. Fletcher Institute for Defense Analyses This review describes a meta- analysis of findings from 50 controlled evaluations of intelligent ...requirements for the meta- analysis : six evaluations with nonconventional control groups and four with flawed implementations of intelligent tutoring...hour of intelligent tutoring; the longest provided intelligent tutoring for three semesters, or 48 weeks. Overall Effects For our primary analysis , we

  12. Spontaneous Symmetry Breaking in Quantum Systems. A review for Scholarpedia

    CERN Document Server

    Strocchi, F

    2012-01-01

    The mechanism of spontaneous symmetry breaking in quantum systems is briefly reviewed, rectifying part of the standard wisdom on logical and mathematical grounds. The crucial role of the localization properties of the time evolution for the conclusion of the Goldstone theorem is emphasized.

  13. Progress in electrical energy storage system:A critical review

    Institute of Scientific and Technical Information of China (English)

    Haisheng Chen; Thang Ngoc Cong; Wei Yang; Chunqing Tan; Yongliang Li; Yulong Ding

    2009-01-01

    Electrical energy storage technologies for stationary applications are reviewed.Particular attention is paid to pumped hydroelectric storage,compressed air energy storage,battery,flow battery,fuel cell,solar fuel,superconducting magnetic energy storage, flywheel, capacitor/supercapacitor,and thermal energy torage.Comparison is made among these technologies in terms of technical characteris-tics,applications and deployment status.

  14. Support for designing waste sorting systems: A mini review.

    Science.gov (United States)

    Rousta, Kamran; Ordoñez, Isabel; Bolton, Kim; Dahlén, Lisa

    2017-08-01

    This article presents a mini review of research aimed at understanding material recovery from municipal solid waste. It focuses on two areas, waste sorting behaviour and collection systems, so that research on the link between these areas could be identified and evaluated. The main results presented and the methods used in the articles are categorised and appraised. The mini review reveals that most of the work that offered design guidelines for waste management systems was based on optimising technical aspects only. In contrast, most of the work that focused on user involvement did not consider developing the technical aspects of the system, but was limited to studies of user behaviour. The only clear consensus among the articles that link user involvement with the technical system is that convenient waste collection infrastructure is crucial for supporting source separation. This mini review reveals that even though the connection between sorting behaviour and technical infrastructure has been explored and described in some articles, there is still a gap when using this knowledge to design waste sorting systems. Future research in this field would benefit from being multidisciplinary and from using complementary methods, so that holistic solutions for material recirculation can be identified. It would be beneficial to actively involve users when developing sorting infrastructures, to be sure to provide a waste management system that will be properly used by them.

  15. Waste in health information systems: a systematic review.

    Science.gov (United States)

    Awang Kalong, Nadia; Yusof, Maryati

    2017-05-08

    Purpose The purpose of this paper is to discuss a systematic review on waste identification related to health information systems (HIS) in Lean transformation. Design/methodology/approach A systematic review was conducted on 19 studies to evaluate Lean transformation and tools used to remove waste related to HIS in clinical settings. Findings Ten waste categories were identified, along with their relationships and applications of Lean tool types related to HIS. Different Lean tools were used at the early and final stages of Lean transformation; the tool selection depended on the waste characteristic. Nine studies reported a positive impact from Lean transformation in improving daily work processes. The selection of Lean tools should be made based on the timing, purpose and characteristics of waste to be removed. Research limitations/implications Overview of waste and its category within HIS and its analysis from socio-technical perspectives enabled the identification of its root cause in a holistic and rigorous manner. Practical implications Understanding waste types, their root cause and review of Lean tools could subsequently lead to the identification of mitigation approach to prevent future error occurrence. Originality/value Specific waste models for HIS settings are yet to be developed. Hence, the identification of the waste categories could guide future implementation of Lean transformations in HIS settings.

  16. Nanoparticle-based assays in automated flow systems: A review

    Energy Technology Data Exchange (ETDEWEB)

    Passos, Marieta L.C. [LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313 Porto (Portugal); Pinto, Paula C.A.G., E-mail: ppinto@ff.up.pt [LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313 Porto (Portugal); Santos, João L.M., E-mail: joaolms@ff.up.pt [LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313 Porto (Portugal); Saraiva, M. Lúcia M.F.S., E-mail: lsaraiva@ff.up.pt [LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313 Porto (Portugal); Araujo, André R.T.S. [LAQV, REQUIMTE, Departamento de Ciências Químicas, Faculdade de Farmácia, Universidade do Porto, Rua Jorge Viterbo Ferreira, n° 228, 4050-313 Porto (Portugal); Unidade de Investigação para o Desenvolvimento do Interior, Instituto Politécnico da Guarda, Av. Dr. Francisco de Sá Carneiro, n° 50, 6300-559 Guarda (Portugal)

    2015-08-19

    Nanoparticles (NPs) exhibit a number of distinctive and entrancing properties that explain their ever increasing application in analytical chemistry, mainly as chemosensors, signaling tags, catalysts, analytical signal enhancers, reactive species generators, analyte recognition and scavenging/separation entities. The prospect of associating NPs with automated flow-based analytical is undoubtedly a challenging perspective as it would permit confined, cost-effective and reliable analysis, within a shorter timeframe, while exploiting the features of NPs. This article aims at examining state-of-the-art on continuous flow analysis and microfluidic approaches involving NPs such as noble metals (gold and silver), magnetic materials, carbon, silica or quantum dots. Emphasis is devoted to NP format, main practical achievements and fields of application. In this context, the functionalization of NPs with distinct chemical species and ligands is debated in what concerns the motivations and strengths of developed approaches. The utilization of NPs to improve detector's performance in electrochemical application is out of the scope of this review. The works discussed in this review were published in the period of time comprised between the years 2000 and 2013. - Highlights: • The state of the art of flowing stream systems comprising NPs was reviewed. • The use of different types of nanoparticles in each flow technique is discussed. • The most expressive and profitable applications are summarized. • The main conclusions and future perspectives were compiled in the final section.

  17. Nanobiotechnology and its applications in drug delivery system: a review.

    Science.gov (United States)

    Khan, Imran; Khan, Momin; Umar, Muhammad Naveed; Oh, Deog-Hwan

    2015-12-01

    Nanobiotechnology holds great potential in various regimes of life sciences. In this review, the potential applications of nanobiotechnology in various sectors of nanotechnologies, including nanomedicine and nanobiopharmaceuticals, are highlighted. To overcome the problems associated with drug delivery, nanotechnology has gained increasing interest in recent years. Nanosystems with different biological properties and compositions have been extensively investigated for drug delivery applications. Nanoparticles fabricated through various techniques have elevated therapeutic efficacy, provided stability to the drugs and proved capable of targeting the cells and controlled release inside the cell. Polymeric nanoparticles have shown increased development and usage in drug delivery as well as in diagnostics in recent decades.

  18. Semantic Interoperability in Clinical Decision Support Systems: A Systematic Review.

    Science.gov (United States)

    Marco-Ruiz, Luis; Bellika, Johan Gustav

    2015-01-01

    The interoperability of Clinical Decision Support (CDS) systems with other health information systems has become one of the main limitations to their broad adoption. Semantic interoperability must be granted in order to share CDS modules across different health information systems. Currently, numerous standards for different purposes are available to enable the interoperability of CDS systems. We performed a literature review to identify and provide an overview of the available standards that enable CDS interoperability in the areas of clinical information, decision logic, terminology, and web service interfaces.

  19. Developments in solar still desalination systems: A critical review

    KAUST Repository

    Ayoub, George M.

    2012-10-01

    Solar still desalination uses a sustainable and pollution-free source to produce high-quality water. The main limitation is low productivity and this has been the focus of intensive research. A major concern while increasing productivity is to maintain economic feasibility and simplicity. The authors present a critical review of the research work conducted on solar stills development. Studies addressing each parameter of concern are grouped together and results compared. Novelty in design and newly introduced features are presented. Modeling efforts of flow circulation within the still and methods to estimate internal heat transfer coefficients are discussed and future research needs are outlined. © 2012 Taylor & Francis Group, LLC.

  20. Mobile technology in health information systems - a review.

    Science.gov (United States)

    Zhang, X-Y; Zhang, P-Y

    2016-05-01

    Mobile technology is getting involved in every sphere of life including medical health care. There has been an immense upsurge in mobile phone-based health innovations these days. The expansion of mobile phone networks and the proliferation of inexpensive mobile handsets have made the digital information and communication technology capabilities very handy for the people to exploit if for any utility including health care. The mobile phone based innovations are able to transform weak and under performing health information system into more modern and efficient information system. The present review article will enlighten all these aspects of mobile technology in health care.

  1. Road impacts on the Baca National Wildlife Refuge, Colorado, with emphasis on effects to surface and shallow ground-water hydrology : a literature review

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A review of published research on unpaved road effects on surface-water and shallow ground-water hydrology was undertaken to assist the Baca National Wildlife...

  2. Information overload within the health care system: a literature review.

    Science.gov (United States)

    Hall, Amanda; Walton, Graham

    2004-06-01

    There is a widespread view held by health clinicians that their work effectiveness is impaired by 'information overload.' Building upon a previous work by Wilson, a review of the literature was undertaken to look for the evidence of this. It was found that the literature, particularly in the context of the clinical environment, was limited. This review explores the diverse overarching theories of information overload, effects of the phenomenon that are perceived to occur and proposed solutions to this problem. Many of the papers noted an information explosion but only three authors explicitly attempted to measure both the quantity and the complexity of this information. It was also found that the typology of the information studied was severely limited with most studies exploring information such as guidelines, access to journals, research findings and other knowledge intensive areas. Solutions proposed seem to concentrate on technological means rather than exploring the use of humans either in management of information or as a step in the filtering process.

  3. Radionuclides in fruit systems. A review of experimental studies

    Energy Technology Data Exchange (ETDEWEB)

    Carini, F.; Spalla, S. [Universita Cattolica del Sacro Cuore, Institute of Agricultural and Environmental Chemistry, Faculty of Agricultural Sciences, Via Emilia Parmense 84, I-29100 Piacenza (Italy); Green, N. [NRPB, Chilton, Didcot, Oxfordshire OX11 0RQ (United Kingdom)

    2006-04-15

    Existing information on processes and parameters analysed in experimental studies on fruits was reviewed at the inception of the activities of the IAEA BIOMASS Fruits Working Group. Additional information on experimental studies, collected during the activities of the Group and not included in the Review, is presented and discussed in this paper. Studies on deposition of {sup 14}CO{sub 2}, CO{sup 35}S and {sup 3}H{sub 2}O in the gas phase to apple, raspberry, strawberry and blackcurrant have filled gaps in knowledge of uptake of gaseous pollutants in fruit plants, quantifying processes of deposition, translocation and carry-over between seasons. Measurements over a period of six years on vine plants contaminated via leaves and soil by dry deposition of {sup 137}Cs and {sup 90}Sr have improved knowledge of the processes of direct deposition to fruit, translocation and carry-over of radionuclides from year to year. Additional information is given on soil to fruit transfer of U, Th and Pb for apple and mandarin grown under intensive agricultural conditions. (author)

  4. Radionuclides in fruit systems: A review of experimental studies

    Energy Technology Data Exchange (ETDEWEB)

    Carini, F. [Universita Cattolica del Sacro Cuore, Institute of Agricultural and Environmental Chemistry, Faculty of Agricultural Sciences, Via Emilia Parmense 84, I-29100 Piacenza (Italy)]. E-mail: franca.carini@unicatt.it; Green, N. [NRPB, Chilton, Didcot, Oxfordshire OX11 0RQ (United Kingdom); Spalla, S. [Universita Cattolica del Sacro Cuore, Institute of Agricultural and Environmental Chemistry, Faculty of Agricultural Sciences, Via Emilia Parmense 84, I-29100 Piacenza (Italy)

    2006-04-15

    Existing information on processes and parameters analysed in experimental studies on fruits was reviewed at the inception of the activities of the IAEA BIOMASS Fruits Working Group. Additional information on experimental studies, collected during the activities of the Group and not included in the Review, is presented and discussed in this paper. Studies on deposition of {sup 14}CO{sub 2}, CO{sup 35}S and {sup 3}H{sub 2}O in the gas phase to apple, raspberry, strawberry and blackcurrant have filled gaps in knowledge of uptake of gaseous pollutants in fruit plants, quantifying processes of deposition, translocation and carry-over between seasons. Measurements over a period of six years on vine plants contaminated via leaves and soil by dry deposition of {sup 137}Cs and {sup 9}Sr have improved knowledge of the processes of direct deposition to fruit, translocation and carry-over of radionuclides from year to year. Additional information is given on soil to fruit transfer of U, Th and Pb for apple and mandarin grown under intensive agricultural conditions.

  5. Transfemoral prosthesis suspension systems: a systematic review of the literature.

    Science.gov (United States)

    Gholizadeh, Hossein; Abu Osman, Noor Azuan; Eshraghi, Arezoo; Ali, Sadeeq

    2014-09-01

    The purpose of this study was to find the scientific evidence pertaining to various transfemoral suspension systems to provide selection criteria for clinicians. To this end, databases of PubMed, Web of Science, and ScienceDirect were explored. The following key words, as well as their combinations and synonyms, were used for the search: transfemoral prosthesis, prosthetic suspension, lower limb prosthesis, above-knee prosthesis, prosthetic liner, transfemoral, and prosthetic socket. The study design, research instrument, sampling method, outcome measures, and protocols of articles were reviewed. On the basis of the selection criteria, 16 articles (11 prospective studies and 5 surveys) were reviewed. The main causes of reluctance to prosthesis, aside from energy expenditure, were socket-related problems such as discomfort, perspiration, and skin problems. Osseointegration was a suspension option, yet it is rarely applied because of several drawbacks, such as extended rehabilitation process, risk for fracture, and infection along with excessive cost. In conclusion, no clinical evidence was found as a "standard" system of suspension and socket design for all transfemoral amputees. However, among various suspension systems for transfemoral amputees, the soft insert or double socket was favored by most users in terms of function and comfort.

  6. Dynamic groundwater monitoring networks: a manageable method for reviewing sampling frequency.

    Science.gov (United States)

    Moreau-Fournier, Magali F; Daughney, Christopher J

    2012-12-01

    Optimization of a water quality network through a change in sampling frequency is the only way to increase cost-efficiency without any reduction in the robustness of the data. Existing techniques define optimal sampling frequency based on analysis of historical data from the monitoring network under investigation. Their application to a large network comprised of many sites and many monitored parameters is both technical and challenging. This paper presents a simple non-parametric method for reviewing sampling frequency that is consistent with highly censored environmental data and oriented towards reduction of sampling frequency as a cost-saving measure. Based on simple descriptive statistics, the method is applicable to large networks with long time series and many monitored parameters. The method also provides metrics for interpretation of newly collected data, which enables identification of sites for which a future change in sampling frequency may be necessary, ensuring that the monitoring network is both current and adaptive. Application of this method to the New Zealand National Groundwater Monitoring Programme indicates that reduction of sampling frequency at any site would result in a significant loss of information. This paper also discusses the potential for reducing analysis frequency as an alternative to reduction of sampling frequency.

  7. In situ treatment of mixed contaminants in groundwater: Review of candidate processes

    Energy Technology Data Exchange (ETDEWEB)

    Korte, N.E. [ed.] [Oak Ridge National Lab., Grand Junction, CO (United States); Siegrist, R.L. [ed.] [Oak Ridge National Lab., TN (United States); Ally, M. [and others

    1994-10-01

    This document describes the screening and preliminary evaluation of candidate treatment for use in treating mixed contaminants volatile organic compounds (VOCs) and radionuclides in groundwater. Treating mixed contaminants presents unusual difficulties. Typically, VOCs are the most abundant contaminants, but the presence of radionuclides results in additional health concerns that must be addressed, usually by a treatment approach different from that used for VOCs. Furthermore, the presence of radionuclides may yield mixed solid wastes if the VOCs are treated by conventional means. These issues were specifically addressed in the evaluation of candidate treatment processes for testing in this program. Moreover, because no research or early development of a particular process would be performed, the technology review also focused on technologies that could be readily adapted and integrated for use with mixed contaminants. The objective is to couple emerging or available processes into treatment modules for use in situ. The three year project, to be completed in September 1996, includes a full-scale field demonstration. The findings reported in this document encompass all activities through the treatment process evaluations.

  8. Nutrients removal and recovery in bioelectrochemical systems: a review.

    Science.gov (United States)

    Kelly, Patrick T; He, Zhen

    2014-02-01

    Nutrient removal and recovery has received less attention during the development of bioelectrochemical systems (BES) for energy efficient wastewater treatment, but it is a critical issue for sustainable wastewater treatment. Both nitrogen and phosphorus can be removed and/or recovered in a BES through involving biological processes such as nitrification and bioelectrochemical denitrification, the NH4(+)/NH3 couple affected by the electrolyte pH, or precipitating phosphorus compounds in the high-pH zone adjacent a cathode electrode. This paper has reviewed the nutrients removal and recovery in various BES including microbial fuel cells and microbial electrolysis cells, discussed the influence factors and potential problems, and identified the key challenges for nitrogen and phosphorus removal/recovery in a BES. It expects to give an informative overview of the current development, and to encourage more thinking and investigation towards further development of efficient processes for nutrient removal and recovery in a BES.

  9. Towards Fractal Approach in Healthcare Information Systems: A Review

    Directory of Open Access Journals (Sweden)

    Nawzat S. Ahmed

    2011-01-01

    Full Text Available Recently, traditional information systems need adaption capabilities in order to overcome modifications and maintains of external environment. For that, researchers proposed many solutions from the Fractal method to improve the flexibility and quick adaptive of the system. Computer Information System, as widely used systems, needs modifications and adaptations to real changes. The most important action is to circulate and updating new data and information among the hosts in agent-based information systems. This paper presents the review of using features of fractal method to solve many problems in different fields. The  paper is also suggesting employing fractal features for improving the flexibility and adaption of Healthcare Information System (HIS.

  10. ENERGY FLOWS IN COMPLEX ECOLOGICAL SYSTEMS: A REVIEW

    Institute of Scientific and Technical Information of China (English)

    Jiang ZHANG

    2009-01-01

    Energy flow drives the complex systems to evolve. The allometric scaling as the universal energy flow pattern has been found in different scales of ecological systems. It reflects the general power law relationship between flow and store. The underlying mechanisms of energy flow patterns are explained as the branching transportation networks which can be regarded as the result of systematic optimization of a biological target under constraints. Energy flows in the ecological system may be modelled by the food web model and population dynamics on the network. This paper reviews the latest progress on the energy flow patterns, explanatory models for the allometric scaling and modelling approach of flow and network evolution dynamics in ecology. Furthermore, the possibility of generalizing these flow patterns, modelling approaches to other complex systems is discussed.

  11. Behavior of metal ions in bioelectrochemical systems: A review

    Science.gov (United States)

    Lu, Zhihao; Chang, Dingming; Ma, Jingxing; Huang, Guangtuan; Cai, Lankun; Zhang, Lehua

    2015-02-01

    Bioelectrochemical systems (BESs) have been focused on by many researchers to treat wastewater and recover energy or valuable chemicals from wastes. In BESs, metal ions play an important role in the conductivity of solution, reactors' internal resistance, power generation, chemical production and activity of microorganisms. Additionally, the metal ions are also involved in anodic or cathodic reaction processes directly or indirectly in BESs. This paper reviews the behavior of metal ions in BESs, including (1) increase of the conductivity of electrolyte and decrease of internal resistance, (2) transfer for desalination, (3) enhancement or inhibition of the biocatalysis in anode, (4) improvement of cathodic performance by metal ions through electron acceptance or catalysis in cathodic process and (5) behavior of metal ions on membranes. Moreover, the perspectives of BESs removing heavy metal ions in wastewater or solid waste are discussed to realize recovery, reduction and detoxification simultaneously.

  12. Bio-Inspired Optimization of Sustainable Energy Systems: A Review

    Directory of Open Access Journals (Sweden)

    Yu-Jun Zheng

    2013-01-01

    Full Text Available Sustainable energy development always involves complex optimization problems of design, planning, and control, which are often computationally difficult for conventional optimization methods. Fortunately, the continuous advances in artificial intelligence have resulted in an increasing number of heuristic optimization methods for effectively handling those complicated problems. Particularly, algorithms that are inspired by the principles of natural biological evolution and/or collective behavior of social colonies have shown a promising performance and are becoming more and more popular nowadays. In this paper we summarize the recent advances in bio-inspired optimization methods, including artificial neural networks, evolutionary algorithms, swarm intelligence, and their hybridizations, which are applied to the field of sustainable energy development. Literature reviewed in this paper shows the current state of the art and discusses the potential future research trends.

  13. Towards an Ultimate Battery Thermal Management System: A Review

    Directory of Open Access Journals (Sweden)

    Mohammad Rezwan Khan

    2017-03-01

    Full Text Available The prevailing standards and scientific literature offer a wide range of options for the construction of a battery thermal management system (BTMS. The design of an innovative yet well-functioning BTMS requires strict supervision, quality audit and continuous improvement of the whole process. It must address all the current quality and safety (Q&S standards. In this review article, an effective battery thermal management is sought considering the existing battery Q&S standards and scientific literature. The article contains a broad overview of the current existing standards and literature on a generic compliant BTMS. The aim is to assist in the design of a novel compatible BTMS. Additionally, the article delivers a set of recommendations to make an effective BTMS.

  14. Web-Based Medical Appointment Systems: A Systematic Review

    Science.gov (United States)

    Zhao, Peng; Lavoie, Jaie; Lavoie, Beau James; Simoes, Eduardo

    2017-01-01

    Background Health care is changing with a new emphasis on patient-centeredness. Fundamental to this transformation is the increasing recognition of patients' role in health care delivery and design. Medical appointment scheduling, as the starting point of most non-urgent health care services, is undergoing major developments to support active involvement of patients. By using the Internet as a medium, patients are given more freedom in decision making about their preferences for the appointments and have improved access. Objective The purpose of this study was to identify the benefits and barriers to implement Web-based medical scheduling discussed in the literature as well as the unmet needs under the current health care environment. Methods In February 2017, MEDLINE was searched through PubMed to identify articles relating to the impacts of Web-based appointment scheduling. Results A total of 36 articles discussing 21 Web-based appointment systems were selected for this review. Most of the practices have positive changes in some metrics after adopting Web-based scheduling, such as reduced no-show rate, decreased staff labor, decreased waiting time, and improved satisfaction, and so on. Cost, flexibility, safety, and integrity are major reasons discouraging providers from switching to Web-based scheduling. Patients’ reluctance to adopt Web-based appointment scheduling is mainly influenced by their past experiences using computers and the Internet as well as their communication preferences. Conclusions Overall, the literature suggests a growing trend for the adoption of Web-based appointment systems. The findings of this review suggest that there are benefits to a variety of patient outcomes from Web-based scheduling interventions with the need for further studies. PMID:28446422

  15. Web-Based Medical Appointment Systems: A Systematic Review.

    Science.gov (United States)

    Zhao, Peng; Yoo, Illhoi; Lavoie, Jaie; Lavoie, Beau James; Simoes, Eduardo

    2017-04-26

    Health care is changing with a new emphasis on patient-centeredness. Fundamental to this transformation is the increasing recognition of patients' role in health care delivery and design. Medical appointment scheduling, as the starting point of most non-urgent health care services, is undergoing major developments to support active involvement of patients. By using the Internet as a medium, patients are given more freedom in decision making about their preferences for the appointments and have improved access. The purpose of this study was to identify the benefits and barriers to implement Web-based medical scheduling discussed in the literature as well as the unmet needs under the current health care environment. In February 2017, MEDLINE was searched through PubMed to identify articles relating to the impacts of Web-based appointment scheduling. A total of 36 articles discussing 21 Web-based appointment systems were selected for this review. Most of the practices have positive changes in some metrics after adopting Web-based scheduling, such as reduced no-show rate, decreased staff labor, decreased waiting time, and improved satisfaction, and so on. Cost, flexibility, safety, and integrity are major reasons discouraging providers from switching to Web-based scheduling. Patients' reluctance to adopt Web-based appointment scheduling is mainly influenced by their past experiences using computers and the Internet as well as their communication preferences. Overall, the literature suggests a growing trend for the adoption of Web-based appointment systems. The findings of this review suggest that there are benefits to a variety of patient outcomes from Web-based scheduling interventions with the need for further studies.

  16. Notes on Aging of the Stomatognathic System. A Literature Review

    Directory of Open Access Journals (Sweden)

    Rogelio Cabo García

    2016-06-01

    Full Text Available Aging is a natural process of varying length that occurs similarly in each species. It is a time-dependent process characterized by a progressive increase in the vulnerability and a decrease in the viability of the organism. It is necessary to know the age-related changes in order to diagnose and treat temporomandibular disorders. This literature review aims to provide an update of the main aspects related to aging of the stomatognathic system. An Internet search was conducted using specialized search engines and descriptors related to this subject. Health databases were also consulted. It was concluded that the main characteristics of the temporomandibular joint during aging are degenerative changes, without necessarily causing clinical manifestations and without a linear relationship between age and radiographic changes in condylar morphology. It is suggested that aging of the stomatognathic muscles is related to the depletion of the stem cell pool and the vascular remodeling that occurs with aging, which may be responsible for changes in muscle function.

  17. Novel targeted bladder drug-delivery systems: a review

    Directory of Open Access Journals (Sweden)

    Zacchè MM

    2015-11-01

    Full Text Available Martino Maria Zacchè, Sushma Srikrishna, Linda Cardozo Department of Urogynaecology, King's College Hospital, London, UK Abstract: The objective of pharmaceutics is the development of drugs with increased efficacy and reduced side effects. Prolonged exposure of the diseased tissue to the drug is of crucial importance. Drug-delivery systems (DDSs have been introduced to control rate, time, and place of release. Drugs can easily reach the bladder through a catheter, while systemically administered agents may undergo extensive metabolism. Continuous urine filling and subsequent washout hinder intravesical drug delivery (IDD. Moreover, the low permeability of the urothelium, also described as the bladder permeability barrier, poses a major challenge in the development of the IDD. DDSs increase bioavailability of drugs, therefore improving therapeutic effect and patient compliance. This review focuses on novel DDSs to treat bladder conditions such as overactive bladder, interstitial cystitis, bladder cancer, and recurrent urinary tract infections. The rationale and strategies for both systemic and local delivery methods are discussed, with emphasis on new formulations of well-known drugs (oxybutynin, nanocarriers, polymeric hydrogels, intravesical devices, encapsulated DDSs, and gene therapy. We give an overview of current and future prospects of DDSs for bladder disorders, including nanotechnology and gene therapy. Keywords: drug targeting, drug-delivery system, bladder disorders

  18. Heterotrophic bacteria in drinking water distribution system: a review.

    Science.gov (United States)

    Chowdhury, Shakhawat

    2012-10-01

    The microbiological quality of drinking water in municipal water distribution systems (WDS) depends on several factors. Free residual chlorine and/or chloramines are typically used to minimize bacterial recontamination and/or regrowth in WDS. Despite such preventive measures, regrowth of heterotrophic (HPC) and opportunistic bacteria in bulk water and biofilms has yet to be controlled completely. No approach has shown complete success in eliminating biofilms or HPC bacteria from bulk water and pipe surfaces. Biofilms can provide shelter for pathogenic bacteria and protect these bacteria from disinfectants. Some HPC bacteria may be associated with aesthetic and non-life threatening diseases. Research to date has achieved important success in understanding occurrence and regrowth of bacteria in bulk water and biofilms in WDS. To achieve comprehensive understanding and to provide efficient control against bacteria regrowth, future research on bacteria regrowth dynamics and their implications is warranted. In this study, a review was performed on the literature published in this area. The findings and limitations of these papers are summarized. Occurrences of bacteria in WDS, factors affecting bacteria regrowth in bulk water and biofilms, bacteria control strategies, sources of nutrients, human health risks from bacterial exposure, modelling of bacteria regrowth and methods of bacteria sampling and detection and quantification are investigated. Advances to date are noted, and future research needs are identified. Finally, research directions are proposed to effectively control HPC and opportunistic bacteria in bulk water and biofilms in WDS.

  19. Permeable pavement and stormwater management systems: a review.

    Science.gov (United States)

    Imran, H M; Akib, Shatirah; Karim, Mohamed Rehan

    2013-01-01

    Uncontrolled stormwater runoff not only creates drainage problems and flash floods but also presents a considerable threat to water quality and the environment. These problems can, to a large extent, be reduced by a type of stormwater management approach employing permeable pavement systems (PPS) in urban, industrial and commercial areas, where frequent problems are caused by intense undrained stormwater. PPS could be an efficient solution for sustainable drainage systems, and control water security as well as renewable energy in certain cases. Considerable research has been conducted on the function of PPS and their improvement to ensure sustainable drainage systems and water quality. This paper presents a review of the use of permeable pavement for different purposes. The paper focuses on drainage systems and stormwater runoff quality from roads, driveways, rooftops and parking lots. PPS are very effective for stormwater management and water reuse. Moreover, geotextiles provide additional facilities to reduce the pollutants from infiltrate runoff into the ground, creating a suitable environment for the biodegradation process. Furthermore, recently, ground source heat pumps and PPS have been found to be an excellent combination for sustainable renewable energy. In addition, this study has identified several gaps in the present state of knowledge on PPS and indicates some research needs for future consideration.

  20. Ecosystem Services from Edible Insects in Agricultural Systems: A Review.

    Science.gov (United States)

    Payne, Charlotte L R; Van Itterbeeck, Joost

    2017-02-17

    Many of the most nutritionally and economically important edible insects are those that are harvested from existing agricultural systems. Current strategies of agricultural intensification focus predominantly on increasing crop yields, with no or little consideration of the repercussions this may have for the additional harvest and ecology of accompanying food insects. Yet such insects provide many valuable ecosystem services, and their sustainable management could be crucial to ensuring future food security. This review considers the multiple ecosystem services provided by edible insects in existing agricultural systems worldwide. Directly and indirectly, edible insects contribute to all four categories of ecosystem services as outlined by the Millennium Ecosystem Services definition: provisioning, regulating, maintaining, and cultural services. They are also responsible for ecosystem disservices, most notably significant crop damage. We argue that it is crucial for decision-makers to evaluate the costs and benefits of the presence of food insects in agricultural systems. We recommend that a key priority for further research is the quantification of the economic and environmental contribution of services and disservices from edible insects in agricultural systems.

  1. ORAL MULTIPARTICULATE PULSATILE DRUG DELIVERY SYSTEMS: A REVIEW

    Directory of Open Access Journals (Sweden)

    Shaji Jessy

    2011-02-01

    Full Text Available Pulsatile drug delivery aims to release drugs in a planned pattern i.e. at appropriate time and/or at a suitable site of action. Pharmaceutical invention and research are increasingly focusing on delivery systems which enhance desirable therapeutic objectives while minimising side effects. However, in recent pharmaceutical applications involving pulsatile delivery, multiparticulate dosage forms are gaining much favour over single-unit dosage forms because of their potential benefits like predictable gastric emptying, no risk of dose dumping, flexible release patterns and increased bioavailability with less inter- and intra-subject variability. Based on these, the present review aims to study multiparticulate pulsatile delivery systems, for which the Reservoir systems with rupturable polymeric coatings and Reservoir systems with erodible polymer coatings are primarily involved in the control of release. Multiparticulate drug delivery systems provide tremendous opportunities for designing new controlled and delayed release oral formulations, thus extending the frontier of future pharmaceutical development. The development of low density floating multiparticulate pulsed-release dosage forms possessing gastric retention capabilities has also been addressed with increasing focus on the upcoming multiparticulate-pulsatile technologies being exploited on an industrial scale.

  2. LIPOSOME AS A POTENTIAL DRUG DELIVERY SYSTEM: A REVIEW

    Directory of Open Access Journals (Sweden)

    Dash Tapaswi Rani

    2013-01-01

    Full Text Available Liposomes are microscopic phospholipid vescicles made of lipid bilayer which are the drug carrier for improving the delivery of therapeutic agents. Research on liposome technology has progressed from conventional vesicles (“first-generation liposomes” to “second-generation liposomes”, in which long-circulating liposomes are obtained by modulating the lipid composition, size, and charge of the vesicle. Liposomes with modified surfaces have also been developed using several molecules, such as glycolipids or sialic acid. A significant step in the development of long-circulating liposomes came with inclusion of the synthetic polymer poly-(ethylene glycol (PEG in liposome composition. Due to advancement in liposomal technology a number of liposomal formulations are available in market for clinical use, with gene delivery and cancer therapy and some formulations are under clinical trial. Reformulation of drugs in liposomes has provided an opportunity to enhance the therapeutic indices of various agents mainly through alteration in their biodistribution. This review discusses the basic principles of liposome structures and preparations, evaluation parameters of liposomal formulation, pharmacokinetics of liposomes and liposome-encapsulated drugs, the potential applications of liposomes in drug delivery with examples of formulations approved for clinical use, and the problems associated with further exploitation of this drug delivery system.

  3. Phenolic Acids in Plant-Soil-Microbe System: A Review

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Phenolic acids are very common compounds in pedosphere. The objective of this review was to summarize the current knowledge of the behaviors of phenolic acids in plant-soil-microbe system. When phenolic acids originated from leaching, decomposition and exudation of living and dead plant tissues enter soils, they can react physicochemically with soil particle surfaces and/or incorporate into humic matter. Phenolic acids desorbed from soil particle surfaces and remained in solution phase can be utilized by microbe as carbon sources and absorbed by plants. The degradation products of phenolic acids by microbe include some organic and/or inorganic compounds such as new phenolic acids. In addition, phenolic acids in soils can stimulate population and activity of microbe. Phenolic acids can inhibit plants growth by affecting ion leakage, phytohormone activity, membrane permeability, hydraulic conductivity, net nutrient uptake, and enzyme activity. Behaviors of phenolic acids in soils are influenced by other organic compounds (phenolic acids, methionine, glucose, etc.) and/or inorganic ions. The role of phenolic acids as allelopathic agents should not be neglected only based on their low specific concentrations in natural soils, because numbers and interactions of phenolic acids will increase their allelopathic activities.

  4. Fentanyl Iontophoretic Transdermal System: A Review in Acute Postoperative Pain.

    Science.gov (United States)

    Scott, Lesley J

    2016-04-01

    Fentanyl iontophoretic transdermal system (ITS) [Ionsys(®)] is indicated for the management of acute postoperative pain in adults requiring opioid analgesia in the hospital setting. This article reviews the clinical use of fentanyl ITS for postoperative pain management, and summarizes the pharmacology of fentanyl and the characteristics of the two-component fentanyl ITS (Ionsys(®)) device. In well-designed, multicentre clinical trials, fentanyl ITS was an effective and generally well tolerated method for managing acute postoperative pain in inpatients who had undergone major abdominal, thoracic or orthopaedic surgery. Overall, fentanyl ITS provided equivalent analgesic efficacy to that with morphine patient-controlled intravenous analgesia (PCIA), but was perceived to be more convenient/easier to use than morphine PCIA by patients, nurses and physical therapists. Patients receiving fentanyl ITS also had a greater ability to mobilize after surgery than patients receiving morphine PCIA. In addition, relative to morphine PCIA, fentanyl ITS offers advantages in terms of the noninvasive administrative route (i.e. transdermal needle-free administration), pre-programmed delivery (no risk of programming errors/incorrect dosing) and improved tolerability with regard to the overall incidence of opioid-related adverse events (ORAEs) and some individual ORAEs. Hence, fentanyl ITS is a useful option for the management of acute postoperative pain in adults requiring opioid analgesia in the hospital setting.

  5. Ecosystem Services from Edible Insects in Agricultural Systems: A Review

    Science.gov (United States)

    Payne, Charlotte L. R.; Van Itterbeeck, Joost

    2017-01-01

    Many of the most nutritionally and economically important edible insects are those that are harvested from existing agricultural systems. Current strategies of agricultural intensification focus predominantly on increasing crop yields, with no or little consideration of the repercussions this may have for the additional harvest and ecology of accompanying food insects. Yet such insects provide many valuable ecosystem services, and their sustainable management could be crucial to ensuring future food security. This review considers the multiple ecosystem services provided by edible insects in existing agricultural systems worldwide. Directly and indirectly, edible insects contribute to all four categories of ecosystem services as outlined by the Millennium Ecosystem Services definition: provisioning, regulating, maintaining, and cultural services. They are also responsible for ecosystem disservices, most notably significant crop damage. We argue that it is crucial for decision-makers to evaluate the costs and benefits of the presence of food insects in agricultural systems. We recommend that a key priority for further research is the quantification of the economic and environmental contribution of services and disservices from edible insects in agricultural systems. PMID:28218635

  6. Medical Image Analysis by Cognitive Information Systems - a Review.

    Science.gov (United States)

    Ogiela, Lidia; Takizawa, Makoto

    2016-10-01

    This publication presents a review of medical image analysis systems. The paradigms of cognitive information systems will be presented by examples of medical image analysis systems. The semantic processes present as it is applied to different types of medical images. Cognitive information systems were defined on the basis of methods for the semantic analysis and interpretation of information - medical images - applied to cognitive meaning of medical images contained in analyzed data sets. Semantic analysis was proposed to analyzed the meaning of data. Meaning is included in information, for example in medical images. Medical image analysis will be presented and discussed as they are applied to various types of medical images, presented selected human organs, with different pathologies. Those images were analyzed using different classes of cognitive information systems. Cognitive information systems dedicated to medical image analysis was also defined for the decision supporting tasks. This process is very important for example in diagnostic and therapy processes, in the selection of semantic aspects/features, from analyzed data sets. Those features allow to create a new way of analysis.

  7. Contact lenses as drug controlled release systems: a narrative review

    Directory of Open Access Journals (Sweden)

    Helena Prior Filipe

    2016-06-01

    Full Text Available ABSTRACT Topically applied therapy is the most common way to treat ocular diseases, however given the anatomical and physiological constraints of the eye, frequent dosing is required with possible repercussions in terms of patient compliance. Beyond refractive error correction, contact lenses (CLs have, in the last few decades emerged as a potential ophthalmic drug controlled release system (DCRS. Extensive research is underway to understand how to best modify CLs to increase residence time and bioavailability of drugs within therapeutic levels on the ocular surface.These devices may simultaneously correct ametropia and have a role in managing ophthalmic disorders that can hinder CL wear such as dry eye, glaucoma, ocular allergy and cornea infection and injury. In this narrative review the authors explain how the ocular surface structures determine drug diffusion in the eye and summarize the strategies to enhance drug residence time and bioavailability. They synthesize findings and clinical applications of drug soaked CLs as DCRS combined with delivery diffusion barriers, incorporation of functional monomers, ion related controlled release, molecular imprinting, nanoparticles and layering. The authors draw conclusions about the impact of these novel ophthalmic agents delivery systems in improving drug transport in the target tissue and patient compliance, in reducing systemic absorption and undesired side effects, and discuss future perspectives.

  8. LAND-BASED MOBILE LASER SCANNING SYSTEMS: A REVIEW

    Directory of Open Access Journals (Sweden)

    I. Puente

    2012-09-01

    Full Text Available Mobile mapping has been using various photogrammetric techniques for many years. In recent years, there has been an increase in the number of mobile mapping systems using laser scanners available in the market, partially because of the improvement in GNSS/INS performance for direct georeferencing. In this article, some of the most important land-based mobile laser scanning (MLS systems are reviewed. Firstly, the main characteristics of MLS systems vs. airborne (ALS and terrestrial laser scanning (TLS systems are compared. Secondly, a short overview of the mobile mapping technology is also provided so that the reader can fully grasp the complexity and operation of these devices. As we put forward in this paper, a comparison of different systems is briefly carried out regarding specifications provided by the manufacturers. Focuses on the current research are also addressed with emphasis on the practical applications of these systems. Most of them have been utilized for data collection on road infrastructures or building façades. This article shows that MLS technology is nowadays well established and proven, since the demand has grown to the point that there are several systems suppliers offering their products to satisfy this particular market.

  9. Adaptive Control of Artificial Pancreas Systems - A Review

    Directory of Open Access Journals (Sweden)

    Kamuran Turksoy

    2014-01-01

    Full Text Available Artificial pancreas (AP systems offer an important improvement in regulating blood glucose concentration for patients with type 1 diabetes, compared to current approaches. AP consists of sensors, control algorithms and an insulin pump. Different AP control algorithms such as proportional-integral-derivative, model-predictive control, adaptive control, and fuzzy logic control have been investigated in simulation and clinical studies in the past three decades. The variability over time and complexity of the dynamics of blood glucose concentration, unsteady disturbances such as meals, time-varying delays on measurements and insulin infusion, and noisy data from sensors create a challenging system to AP. Adaptive control is a powerful control technique that can deal with such challenges. In this paper, a review of adaptive control techniques for blood glucose regulation with an AP system is presented. The investigations and advances in technology produced impressive results, but there is still a need for a reliable AP system that is both commercially viable and appealing to patients with type 1 diabetes.

  10. Land-Based Mobile Laser Scanning Systems: a Review

    Science.gov (United States)

    Puente, I.; González-Jorge, H.; Arias, P.; Armesto, J.

    2011-09-01

    Mobile mapping has been using various photogrammetric techniques for many years. In recent years, there has been an increase in the number of mobile mapping systems using laser scanners available in the market, partially because of the improvement in GNSS/INS performance for direct georeferencing. In this article, some of the most important land-based mobile laser scanning (MLS) systems are reviewed. Firstly, the main characteristics of MLS systems vs. airborne (ALS) and terrestrial laser scanning (TLS) systems are compared. Secondly, a short overview of the mobile mapping technology is also provided so that the reader can fully grasp the complexity and operation of these devices. As we put forward in this paper, a comparison of different systems is briefly carried out regarding specifications provided by the manufacturers. Focuses on the current research are also addressed with emphasis on the practical applications of these systems. Most of them have been utilized for data collection on road infrastructures or building façades. This article shows that MLS technology is nowadays well established and proven, since the demand has grown to the point that there are several systems suppliers offering their products to satisfy this particular market.

  11. Photoelectrochemical cells based on photosynthetic systems: a review

    Directory of Open Access Journals (Sweden)

    Roman A. Voloshin

    2015-06-01

    Full Text Available Photosynthesis is a process which converts light energy into energy contained in the chemical bonds of organic compounds by photosynthetic pigments such as chlorophyll (Chl a, b, c, d, f or bacteriochlorophyll. It occurs in phototrophic organisms, which include higher plants and many types of photosynthetic bacteria, including cyanobacteria. In the case of the oxygenic photosynthesis, water is a donor of both electrons and protons, and solar radiation serves as inexhaustible source of energy. Efficiency of energy conversion in the primary processes of photosynthesis is close to 100%. Therefore, for many years photosynthesis has attracted the attention of researchers and designers looking for alternative energy systems as one of the most efficient and eco-friendly pathways of energy conversion. The latest advances in the design of optimal solar cells include the creation of converters based on thylakoid membranes, photosystems, and whole cells of cyanobacteria immobilized on nanostructured electrode (gold nanoparticles, carbon nanotubes, nanoparticles of ZnO and TiO2. The mode of solar energy conversion in photosynthesis has a great potential as a source of renewable energy while it is sustainable and environmentally safety as well. Application of pigments such as Chl f and Chl d (unlike Chl a and Chl b, by absorbing the far red and near infrared region of the spectrum (in the range 700-750 nm, will allow to increase the efficiency of such light transforming systems. This review article presents the last achievements in the field of energy photoconverters based on photosynthetic systems.

  12. Vasculitides and the Complement System: a Comprehensive Review.

    Science.gov (United States)

    Chimenti, Maria Sole; Ballanti, Eleonora; Triggianese, Paola; Perricone, Roberto

    2015-12-01

    Systemic vasculitides are a group of rare diseases characterized by inflammation of the arterial or venous vessel wall, causing stenosis or thrombosis. Clinical symptoms may be limited to skin or to other organs or may include multiple manifestations as systemic conditions. The pathogenesis is related to the presence of leukocytes in the vessels and to the IC deposition, which implies the activation of the complement system (CS) and then the swelling and damage of vessel mural structures. The complement system (CS) is involved in the pathogenesis of several autoimmune diseases, including systemic vasculitides. This enzymatic system is a part of the innate immune system, and its function is linked to the modulation of the adaptive immunity and in bridging innate and adaptive responses. Its activation is also critical for the development of natural antibodies and T cell response and for the regulation of autoreactive B cells. Complement triggering contributes to inflammation-driven tissue injury, which occurs during the ischemia/reperfusion processes, vasculitides, nephritis, arthritis, and many others diseases. In systemic vasculitides, a group of uncommon diseases characterized by blood vessel inflammation, the contribution of CS in the development of inflammatory damage has been demonstrated. Treatment is mainly based on clinical manifestations and severity of organ involvement. Evidences on the efficacy of traditional immunosuppressive therapies have been collected as well as data from clinical trials that involve the modulation of the CS. In particular in small-medium-vessel vasculitides, the CS represents an attractive target. Herein, we reviewed the pathogenetic role of CS in these systemic vasculitides as urticarial vasculitis, ANCA-associated vasculitides, anti-glomerular basement membrane disease, cryoglobulinaemic vasculitides, Henoch-Schönlein purpura/IgA nephropathy, and Kawasaki disease and therefore its potential therapeutic use in this context.

  13. Review: Regional groundwater flow modeling in heavily irrigated basins of selected states in the western United States

    Science.gov (United States)

    Rossman, Nathan R.; Zlotnik, Vitaly A.

    2013-09-01

    Water resources in agriculture-dominated basins of the arid western United States are stressed due to long-term impacts from pumping. A review of 88 regional groundwater-flow modeling applications from seven intensively irrigated western states (Arizona, California, Colorado, Idaho, Kansas, Nebraska and Texas) was conducted to provide hydrogeologists, modelers, water managers, and decision makers insight about past modeling studies that will aid future model development. Groundwater models were classified into three types: resource evaluation models (39 %), which quantify water budgets and act as preliminary models intended to be updated later, or constitute re-calibrations of older models; management/planning models (55 %), used to explore and identify management plans based on the response of the groundwater system to water-development or climate scenarios, sometimes under water-use constraints; and water rights models (7 %), used to make water administration decisions based on model output and to quantify water shortages incurred by water users or climate changes. Results for 27 model characteristics are summarized by state and model type, and important comparisons and contrasts are highlighted. Consideration of modeling uncertainty and the management focus toward sustainability, adaptive management and resilience are discussed, and future modeling recommendations, in light of the reviewed models and other published works, are presented.

  14. Biostrategic Removal of Sulphur Contamination in Groundwater With Sulphur-Reducing Bacteria: A Review

    Directory of Open Access Journals (Sweden)

    Sandeep Satapathy

    2017-02-01

    Full Text Available The rapid growth in the use of fertilizers and pesticides in agriculture, excessive extraction of groundwater, and rise in the number of industries with inefficient waste disposal system have been some of the key factors in degradation of groundwater quality during the past years. Although groundwater is considered as a valuable natural resource, the quality control of this resource has systematically failed in India. Irrespective of rural or urban locations, the average sulphate contamination of groundwater in India has reached 90 to 150 mg/L. Such a borderline contamination concentration poses threat both to livelihood and to economy. In addition, the negative health effects of sulphate-contaminated drinking water can range from dermatitis to lung problems and skin cancer. The biostrategic manipulation of groundwater discussed in this article involves sulphate-reducing bacteria used in addition to a 3-step procedure involving constitutive aeration, filtration, and shock chlorination. With earlier use of a similar strategy in the United States and Europe proven to be beneficial, we propose a combinatorial and economical approach for processing of groundwater for removal of sulphur contamination, which still largely remains unnoticed and neglected.

  15. Contamination of Groundwater Systems in the US and Canada by Enteric Pathogens, 1990–2013: A Review and Pooled-Analysis

    Science.gov (United States)

    Hynds, Paul Dylan; Thomas, M. Kate; Pintar, Katarina Dorothy Milena

    2014-01-01

    Background Up to 150 million North Americans currently use a groundwater system as their principal drinking water source. These systems are a potential source of exposure to enteric pathogens, contributing to the burden of waterborne disease. Waterborne disease outbreaks have been associated with US and Canadian groundwater systems over the past two decades. However, to date, this literature has not been reviewed in a comprehensive manner. Methods and Principal Findings A combined review and pooled-analysis approach was used to investigate groundwater contamination in Canada and the US from 1990 to 2013; fifty-five studies met eligibility criteria. Four study types were identified. It was found that study location affects study design, sample rate and studied pathogen category. Approximately 15% (316/2210) of samples from Canadian and US groundwater sources were positive for enteric pathogens, with no difference observed based on system type. Knowledge gaps exist, particularly in exposure assessment for attributing disease to groundwater supplies. Furthermore, there is a lack of consistency in risk factor reporting (local hydrogeology, well type, well use, etc). The widespread use of fecal indicator organisms in reported studies does not inform the assessment of human health risks associated with groundwater supplies. Conclusions This review illustrates how groundwater study design and location are critical for subsequent data interpretation and use. Knowledge gaps exist related to data on bacterial, viral and protozoan pathogen prevalence in Canadian and US groundwater systems, as well as a need for standardized approaches for reporting study design and results. Fecal indicators are examined as a surrogate for health risk assessments; caution is advised in their widespread use. Study findings may be useful during suspected waterborne outbreaks linked with a groundwater supply to identify the likely etiological agent and potential transport pathway. PMID:24806545

  16. A review of arsenic and its impacts in groundwater of the Ganges-Brahmaputra-Meghna delta, Bangladesh.

    Science.gov (United States)

    Edmunds, W M; Ahmed, K M; Whitehead, P G

    2015-06-01

    Arsenic in drinking water is the single most important environmental issue facing Bangladesh; between 35 and 77 million of its 156 million inhabitants are considered to be at risk from drinking As-contaminated water. This dominates the list of stress factors affecting health, livelihoods and the ecosystem of the delta region. There is a vast literature on the subject so this review provides a filter of the more important information available on the topic. The arsenic problem arises from the move in the 1980s and 1990s by international agencies to construct tube wells as a source of water free of pathogens, groundwater usually considered a safe source. Since arsenic was not measured during routine chemical analysis and also is difficult to measure at low concentrations it was not until the late 1990s that the widespread natural anomaly of high arsenic was discovered and confirmed. The problem was exacerbated by the fact that the medical evidence of arsenicosis only appears slowly. The problem arises in delta regions because of the young age of the sediments deposited by the GBM river system. The sediments contain minerals such as biotite which undergo slow "diagenetic" reactions as the sediments become compacted, and which, under the reducing conditions of the groundwater, release in the form of toxic As(3+). The problem is restricted to sediments of Holocene age and groundwater of a certain depth (mainly 30-150 m), coinciding with the optimum well depth. The problem is most serious in a belt across southern Bangladesh, but within 50 m of the coast the problem is only minor because of use of deep groundwater; salinity in shallow groundwater here is the main issue for drinking water. The Government of Bangladesh adopted a National Arsenic Policy and Mitigation Action Plan in 2004 for providing arsenic safe water to all the exposed population, to provide medical care for those who have visible symptoms of arsenicosis. There is as yet no national monitoring program in

  17. A Review of Groundwater Quality Issue in Jharkhand Due to Fluoride

    Directory of Open Access Journals (Sweden)

    Neeta Kumari

    2014-07-01

    Full Text Available Water is elixir of life. Water resources are categorized as surface sources and Groundwater sources. The groundwater have certain dissolved ions , among which presence of fluoride has got significance as it is required by the human body for mineralization of bones and formation of enamel. As per the WHO standard prescribe maximum level for fluoride in drinking water, is 1.5 mg/l, and IS : 10500 specifies required desirable limit of fluoride concentration in drinking water as 0.6-1.0 mg/L, maximum limit is extended to 1.5 mg/l. In the study area, Jharkhand, Palamu, Garhwa, Giridih, Bokaro, Gumla, Godda, Ranchi are the districts where fluoride pollution in water is prevalent. The Daltonganj block in Palamu district is severely affected by this problem. The fluoride problem in the area is mainly geogenic. Other factors like pH, climatic conditions also play a major role.

  18. Arsenic in groundwater of the Kolkata Municipal Corporation (KMC), India: Critical review and modes of mitigation.

    Science.gov (United States)

    Chakraborti, Dipankar; Das, Bhaskar; Rahman, Mohammad Mahmudur; Nayak, Bishwajit; Pal, Arup; Sengupta, Mrinal K; Ahamed, Sad; Hossain, Md Amir; Chowdhury, Uttam K; Biswas, Bhajan Kumar; Saha, Khitish Chandra; Dutta, R N

    2017-08-01

    This study represents the first comprehensive report of groundwater arsenic contamination status in the Kolkata Municipal Corporation (KMC). During the past 23 years, 4210 groundwater samples were analysed from all 141 wards in the KMC: 14.2% and 5.2% samples had arsenic >10 μg/l and >50 μg/l, respectively, representing 77 and 37 wards. The study shows that the number of arsenic contaminated samples (and wards) in the southern part of the KMC exceeds that of other parts of the city. The daily intake of arsenic from drinking water was estimated as 0.95 μg per kg bw and the cancer risk was estimated as 1425/10(6). Analyses of biological samples (hair, nail and urine) showed elevated concentrations of arsenic indicating the presence of subclinical arsenic poisoning, predicting an enhanced lifetime cancer risk for the population in southern part of the KMC. In the KMC, groundwater is not a sustainable source of freshwater due to arsenic, high iron, hardness and total dissolved solids. Its continued use is impelled by the lack of an adequate infrastructure to treat and supply surface water and in some wards the unaccounted for water (UFW) is even >45% incurred during distribution. The rare imposition of a water tax makes the water supply systems unsustainable and fosters indifference to water conservation. To mitigate the arsenic problem, continuous groundwater monitoring for pollutants, a treated surface water supply with strict policy implications, rainwater harvesting in the urban areas and introduction of water taxes seem to be long-term visible solutions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Groundwater resources in Brazil: a review of possible impacts caused by climate change.

    Science.gov (United States)

    Hirata, Ricardo; Conicelli, Bruno P

    2012-06-01

    Groundwater has a strategic role in times of climate change mainly because aquifers can provide water for long periods, even during very long and severe drought. The reduction and/or changes on the precipitation pattern can diminish the recharge mainly in unconfined aquifer, causing available groundwater restriction. The expected impact of long-term climate changes on the Brazilian aquifers for 2050 will lead to a severe reduction in 70% of recharge in the Northeast region aquifers (comparing to 2010 values), varying from 30% to 70% in the North region. Data referring to the South and Southeast regions are more favorable, with an increase in the relative recharge values from 30% to 100%. Another expected impact is the increase in demand and the decrease in the surface water availability that will make the population turn to aquifers as its main source of water for public or private uses in many regions of the country. Thus, an integrated use of surface and groundwater must therefore be considered in the water use planning. The solution of water scarcity is based on three factors: society growth awareness, better knowledge on the characteristics of hydraulic and chemical aquifers and effective management actions.

  20. Integration goes underground: A review of groundwater research in support of sustainable development in South Africa

    CSIR Research Space (South Africa)

    Colvin, C

    2008-11-01

    Full Text Available (approximately 5 000) in South Africa yield groundwater with greater than 10 mg/L no3-n. these are shown in Figure 1. High levels of nitrate in drinking water may cause methaemoglobinaemia or Blue Baby syndrome (wHo, 1993) and death of livestock...-gradient of the well field while some 4000 m3/d higher salinity industrial wastewater is treated and discharged into basins down gradient of the well field close to the ocean without further use for recharge. Hydrochemical monitoring of the various water sources has...

  1. Groundwater socio-ecology and governance: a review of institutions and policies in selected countries

    Science.gov (United States)

    Mukherji, Aditi; Shah, Tushaar

    2005-03-01

    Groundwater is crucial for the livelihoods and food security of millions of people, and yet, knowledge formation in the field of groundwater has remained asymmetrical. While, scientific knowledge in the discipline (hydrology and hydrogeology) has advanced remarkably, relatively little is known about the socio-economic impacts and institutions that govern groundwater use. This paper therefore has two objectives. The first is to provide a balanced view of the plus and the down side of groundwater use, especially in agriculture. In doing so, examples are drawn from countries such as India, Pakistan, Bangladesh, China, Spain and Mexico—all of which make very intensive use of groundwater. Second, institutions and policies that influence groundwater use are analyzed in order to understand how groundwater is governed in these countries and whether successful models of governance could be replicated elsewhere. Finally, the authors argue that there is a need for a paradigm shift in the way groundwater is presently perceived and managed—from management to governance mode. In this attempt, a number of instruments such as direct regulation, indirect policy levers, livelihood adaptation and people's participation will have to be deployed simultaneously in a quest for better governance. L'eau souterraine est cruciale pour la survie et la sécurité alimentaire de plusieurs millions de personnes mais cependant la foramtion en matière d'eaux souterraines reste asymmétrique. Alors que la connaissance scientifique dans la discipline (hydrologie et hydrogéologie) a avancée de manière remarquable, on connaît peu de choses sur les impacts socio-économiques et les institutions qui gouvernent l'utilisation des eaux souterraines. Cet article a par conséquent deux objectifs. Le premier est d'assurer un point de vue balancé entre le côté positif et le côté négatif de l'utilisation de l'eau souterraine, spécialement en agriculture. De cette manière, des exemples d

  2. Review: Moisture loading—the hidden information in groundwater observation well records

    Science.gov (United States)

    van der Kamp, Garth; Schmidt, Randy

    2017-07-01

    Changes of total moisture mass above an aquifer such as snow accumulation, soil moisture, and storage at the water table, represent changes of mechanical load acting on the aquifer. The resulting moisture-loading effects occur in all observation well records for confined aquifers. Deep observation wells therefore act as large-scale geological weighing lysimeters, referred to as "geolysimeters". Barometric pressure effects on groundwater levels are a similar response to surface loading and are familiar to every hydrogeologist dealing with the "barometric efficiency" of observation wells. Moisture-loading effects are small and generally not recognized because they are obscured by hydraulic head fluctuations due to other causes, primarily barometric pressure changes. For semiconfined aquifers, long-term moisture-loading effects may be dissipated and obscured by transient flow through overlying aquitards. Removal of barometric and earth tide effects from observation well records allows identification of moisture loading and comparison with hydrological observations, and also comparison with the results of numerical models that can account for transient groundwater flow.

  3. Water Quality Improvement Performance of Geotextiles Within Permeable Pavement Systems: A Critical Review

    Directory of Open Access Journals (Sweden)

    Miklas Scholz

    2013-04-01

    Full Text Available Sustainable drainage systems (SuDS; or best management practices are increasingly being used as ecological engineering techniques to prevent the contamination of receiving watercourses and groundwater. Permeable paving is a SuDS technique, which is commonplace in car parks, driveways and minor roads where one of their functions is to improve the quality of urban runoff. However, little is known about the water quality benefits of incorporating an upper geotextile within the paving structure. The review focuses on five different categories of pollutants: organic matter, nutrients, heavy metals, motor oils, suspended solids originating from street dust, and chloride. The paper critically assesses results from previous international tests and draws conclusions on the scientific rigour and significance of the data. Findings indicate that only very few studies have been undertaken to address the role of geotextiles directly. All indications are that the presence of a geotextile leads only to minor water quality improvements. For example, suspended solids are being held back by the geotextile and these solids sometimes contain organic matter, nutrients and heavy metals. However, most studies were inconclusive and data were often unsuitable for further statistical analysis. Further long-term research on industry-relevant, and statistically and scientifically sound, experimental set-ups is recommended.

  4. Promising approaches to the purification of soils and groundwater from hydrocarbons (A Review)

    Science.gov (United States)

    Vodyanitskii, Yu. N.; Trofimov, S. Ya.; Shoba, S. A.

    2016-06-01

    Soils and waters are affected by oil spills in the course of oil production and hydrocarbon leakages because of the corrosion of underground reservoirs, as well as the filtration of hydrocarbons from the tailing ponds formed during the extraction of oil from oil sands. The conventional technology for the withdrawal of contaminated water and its purification on the surface is low-efficient and expensive. New approaches are proposed for the in situ purification of soils and groundwater. To accelerate the oxidation, active substances atypical for the supergenesis zone are used: peroxides of metals and hydrogen. The efficiency of hydrogen peroxide significantly increases when the oxidation is catalyzed by Fe2+ or Fe3+ (Fenton reaction). The effects of Fe(III), sulfates, and carbon dioxide as electron acceptors are studied under anaerobic conditions (with oxygen deficit).

  5. Review of strategies for handling geological uncertainty in groundwater flow and transport modeling

    DEFF Research Database (Denmark)

    Refsgaard, Jens Christian; Christensen, Steen; Sonnenborg, Torben O.;

    2012-01-01

    The geologically related uncertainty in groundwater modeling originates from two main sources: geological structures and hydraulic parameter values within these structures. Within a geological structural element the parameter values will always exhibit local scale heterogeneity, which can...... be accounted for, but is often neglected, in assessments of prediction uncertainties. Strategies for assessing prediction uncertainty due to geologically related uncertainty may be divided into three main categories, accounting for uncertainty due to: (a) the geological structure; (b) effective model...... parameters; and (c) model parameters including local scale heterogeneity. The most common methodologies for uncertainty assessments within each of these categories, such as multiple modeling, Monte Carlo analysis, regression analysis and moment equation approach, are briefly described with emphasis...

  6. Contamination of soils and groundwater with new organic micropollutants: A review

    Science.gov (United States)

    Vodyanitskii, Yu. N.; Yakovlev, A. S.

    2016-05-01

    The input of organic micro- and nanopollutants to the environment has grown in recent years. This vast class of substances is referred to as emerging micropollutants, and includes organic chemicals of industrial, agricultural, and municipal provenance. There are three main sources of emerging pollutants coming to the environment, i.e., (1) upon soil fertilization with sewage and sewage sludge; (2) soil irrigation with reclaimed wastewater and (3) due to filtration from municipal landfills of solid wastes. These pollutants contaminate soil, affect its inhabitants; they are also consumed by plants and penetrate to the groundwater. The pharmaceuticals most strongly affect the biota (microorganisms, earthworms, etc.). The response of microorganisms in the contaminated soil is controlled not only by the composition and the number of emerging pollutants but also by the geochemical environment.

  7. 40 CFR 265.91 - Ground-water monitoring system.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 25 2010-07-01 2010-07-01 false Ground-water monitoring system. 265.91... DISPOSAL FACILITIES Ground-Water Monitoring § 265.91 Ground-water monitoring system. (a) A ground-water monitoring system must be capable of yielding ground-water samples for analysis and must consist of: (1...

  8. A review of single-sample-based models and other approaches for radiocarbon dating of dissolved inorganic carbon in groundwater

    Science.gov (United States)

    Han, L. F; Plummer, Niel

    2016-01-01

    Numerous methods have been proposed to estimate the pre-nuclear-detonation 14C content of dissolved inorganic carbon (DIC) recharged to groundwater that has been corrected/adjusted for geochemical processes in the absence of radioactive decay (14C0) - a quantity that is essential for estimation of radiocarbon age of DIC in groundwater. The models/approaches most commonly used are grouped as follows: (1) single-sample-based models, (2) a statistical approach based on the observed (curved) relationship between 14C and δ13C data for the aquifer, and (3) the geochemical mass-balance approach that constructs adjustment models accounting for all the geochemical reactions known to occur along a groundwater flow path. This review discusses first the geochemical processes behind each of the single-sample-based models, followed by discussions of the statistical approach and the geochemical mass-balance approach. Finally, the applications, advantages and limitations of the three groups of models/approaches are discussed.The single-sample-based models constitute the prevailing use of 14C data in hydrogeology and hydrological studies. This is in part because the models are applied to an individual water sample to estimate the 14C age, therefore the measurement data are easily available. These models have been shown to provide realistic radiocarbon ages in many studies. However, they usually are limited to simple carbonate aquifers and selection of model may have significant effects on 14C0 often resulting in a wide range of estimates of 14C ages.Of the single-sample-based models, four are recommended for the estimation of 14C0 of DIC in groundwater: Pearson's model, (Ingerson and Pearson, 1964; Pearson and White, 1967), Han & Plummer's model (Han and Plummer, 2013), the IAEA model (Gonfiantini, 1972; Salem et al., 1980), and Oeschger's model (Geyh, 2000). These four models include all processes considered in single-sample-based models, and can be used in different ranges of

  9. Review of Risk Status of Groundwater Supply Wells by Tracing the Source of Coliform Contamination

    Directory of Open Access Journals (Sweden)

    Nara Somaratne

    2015-07-01

    Full Text Available Coliform source tracking was undertaken on 48 water sources of which 42 are potable in 26 water supply systems spread across South Australia. The water sources in the study vary from unprotected springs in creek beds to deep confined aquifers. The frequency analysis of historical coliform detections indicate that aquifer types, depth to water and casing depth are important considerations; whilst maintaining well integrity and the presence of low permeable clay layers above the production zone are the dominant parameters for minimizing coliform contamination of water supply wells. However, in karst and fractured rock aquifers, pathways for coliform transport exist, as evidenced in the >200 MPN/100 mL level of coliform detection. Data indicate that there is no compelling evidence to support the contention that the wells identified as low risk are contaminated through geological strata and clay barriers. However, data strongly supports the suggestion that coliform detection from sample taps and wellheads stem from the surrounding groundwater and soil-plant sources as a result of failed well integrity, or potentially from coliform bacteria that can persist within biofilms formed on well casings, screens, pump columns and pumps. Coliform sub-typing results show that most coliform bacteria detected in town water supply wells are associated with the soil-water-plant system and are ubiquitous in the environment: Citrobacter spp. (65%, Enterobacter spp. (63%, Pantoea spp. (17%, Serratia spp. (19%, Klebsiella spp. (34%, and Pseudomonas spp. (10%. Overall, 70% of wells harbor detectable thermotolerant coliforms (TTC with potentially 36% of species of animal origin, including Escherichia coli species found in 12% of wells.

  10. Hydrological and geochemical processes constraining groundwater salinity in wetland areas related to evaporitic (karst) systems. A case study from Southern Spain

    Science.gov (United States)

    Gil-Márquez, J. M.; Barberá, J. A.; Andreo, B.; Mudarra, M.

    2017-01-01

    Chemical and isotopic evolution of groundwater in an evaporite karst plateau (including wetland areas and saline to hyper-saline springs) located at S Spain was studied. Physicochemical parameters, major ions and stable isotopes were analyzed in rain, brine spring, wetland and leakage water samples, from which the most common mineral saturation indexes were computed and geochemical and isotopic modelling were performed. Results show an apparent relationship between the elevation of brine springs and their water mineralization, indicating that drainage at higher altitude may be associated to gravity-driven flows, since brackish groundwater is isotopically fractionated due to evaporation. On the other hand, the lower altitude springs could drain deeper flows with longer residence time, resulting in highly mineralized and warmer (briny) groundwater. The dissolution of halite and gypsum has proved to be the main geochemical processes, which are favored by the great ionic strength of groundwater. Calcite precipitation occurs in brackish waters draining wetlands, being boosted by common ion effect (when CaSO4 waters are present) and solute concentration caused by evaporation. Modelling results strongly support the hypothesis that most of the selected springs geochemically evolve in a common (S-N) flowpath. The methods used in this research contribute to a better understanding of the hydrogeological processes occurring in the studied evaporitic system, but also in equivalent hydrological environments worldwide.

  11. Life cycle assessment of soil and groundwater remediation technologies: literature review

    DEFF Research Database (Denmark)

    Lemming, Gitte; Hauschild, Michael Zwicky; Bjerg, Poul Løgstrup

    2010-01-01

    Background, aim, and scope Life cycle assessment (LCA) is becoming an increasingly widespread tool in support systems for environmental decision-making regarding the cleanup of contaminated sites. In this study, the use of LCA to compare the environmental impacts of different remediation...... and scope definition and the applied impact assessment. The studies differ in their basic approach since some are prospective with focus on decision support while others are retrospective aiming at a more detailed assessment of a completed remediation project. Literature review The literature review showed...... scenarios in terms of their associated environmental burden. Main features An overview of the assessed remediation technologies and contaminant types covered in the literature is presented. The LCA methodologies of the 12 reviewed studies were compared and discussed with special focus on their goal...

  12. Review: Satellite-based remote sensing and geographic information systems and their application in the assessment of groundwater potential, with particular reference to India

    Science.gov (United States)

    Jasmin, Ismail; Mallikarjuna, P.

    2011-06-01

    Various hydrological, geological and geomorphological factors play a major role in the occurrence and movement of groundwater in different terrains. With advances in space technology and the advent of powerful personal computers, techniques for the assessment of groundwater potential have evolved, of which remote sensing (RS) and geographic information systems (GIS) are of great significance. The application of these methods is comprehensively reviewed with respect to the exploration and assessment of groundwater potential in consolidated and unconsolidated formations in semi-arid regions, and specifically in India. The process of such assessment includes the collection of remotely sensed data from suitable sensors and the selection of thematic maps on rainfall, geology, lithology, geomorphology, soil, land use/land cover, drainage patterns, slope and lineaments. The data are handled according to their significance with the assignment of appropriate weights and integrated into a sophisticated GIS environment. The requisite remote sensing and GIS data, in conjunction with necessary field investigations, help to identify the groundwater potential zones effectively.

  13. Groundwater-fed irrigation impacts spatially distributed temporal scaling behavior of the natural system: a spatio-temporal framework for understanding water management impacts

    Science.gov (United States)

    Condon, Laura E.; Maxwell, Reed M.

    2014-03-01

    Regional scale water management analysis increasingly relies on integrated modeling tools. Much recent work has focused on groundwater-surface water interactions and feedbacks. However, to our knowledge, no study has explicitly considered impacts of management operations on the temporal dynamics of the natural system. Here, we simulate twenty years of hourly moisture dependent, groundwater-fed irrigation using a three-dimensional, fully integrated, hydrologic model (ParFlow-CLM). Results highlight interconnections between irrigation demand, groundwater oscillation frequency and latent heat flux variability not previously demonstrated. Additionally, the three-dimensional model used allows for novel consideration of spatial patterns in temporal dynamics. Latent heat flux and water table depth both display spatial organization in temporal scaling, an important finding given the spatial homogeneity and weak scaling observed in atmospheric forcings. Pumping and irrigation amplify high frequency (sub-annual) variability while attenuating low frequency (inter-annual) variability. Irrigation also intensifies scaling within irrigated areas, essentially increasing temporal memory in both the surface and the subsurface. These findings demonstrate management impacts that extend beyond traditional water balance considerations to the fundamental behavior of the system itself. This is an important step to better understanding groundwater’s role as a buffer for natural variability and the impact that water management has on this capacity.

  14. Review of inputs provided to Jason Associates Corporation in support of RWEV-REP-001, the Analysis of Postclosure Groundwater Impacts report.

    Energy Technology Data Exchange (ETDEWEB)

    Bryan, Charles R.; Weck, Philippe F.; Vaughn, Palmer; Arnold, Bill Walter

    2014-04-01

    Report RWEV-REP-001, Analysis of Postclosure Groundwater Impacts for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High Level Radioactive Waste at Yucca Mountain, Nye County, Nevada was issued by the DOE in 2009 and is currently being updated. Sandia National Laboratories (SNL) provided support for the original document, performing calculations and extracting data from the Yucca Mountain Performance Assessment Model that were used as inputs to the contaminant transport and dose calculations by Jason Associates Corporation, the primary developers of the DOE report. The inputs from SNL were documented in LSA-AR-037, Inputs to Jason Associates Corporation in Support of the Postclosure Repository Supplemental Environmental Impact Statement. To support the updating of the original Groundwater Impacts document, SNL has reviewed the inputs provided in LSA-AR-037 to verify that they are current and appropriate for use. The results of that assessment are documented here.

  15. Review of quantitative surveys of the length and stability of MTBE, TBA, and benzene plumes in groundwater at UST sites.

    Science.gov (United States)

    Connor, John A; Kamath, Roopa; Walker, Kenneth L; McHugh, Thomas E

    2015-01-01

    Quantitative information regarding the length and stability condition of groundwater plumes of benzene, methyl tert-butyl ether (MTBE), and tert-butyl alcohol (TBA) has been compiled from thousands of underground storage tank (UST) sites in the United States where gasoline fuel releases have occurred. This paper presents a review and summary of 13 published scientific surveys, of which 10 address benzene and/or MTBE plumes only, and 3 address benzene, MTBE, and TBA plumes. These data show the observed lengths of benzene and MTBE plumes to be relatively consistent among various regions and hydrogeologic settings, with median lengths at a delineation limit of 10 µg/L falling into relatively narrow ranges from 101 to 185 feet for benzene and 110 to 178 feet for MTBE. The observed statistical distributions of MTBE and benzene plumes show the two plume types to be of comparable lengths, with 90th percentile MTBE plume lengths moderately exceeding benzene plume lengths by 16% at a 10-µg/L delineation limit (400 feet vs. 345 feet) and 25% at a 5-µg/L delineation limit (530 feet vs. 425 feet). Stability analyses for benzene and MTBE plumes found 94 and 93% of these plumes, respectively, to be in a nonexpanding condition, and over 91% of individual monitoring wells to exhibit nonincreasing concentration trends. Three published studies addressing TBA found TBA plumes to be of comparable length to MTBE and benzene plumes, with 86% of wells in one study showing nonincreasing concentration trends.

  16. Review Team Focused Modeling Analysis of Radial Collector Well Operation on the Hypersaline Groundwater Plume beneath the Turkey Point Site near Homestead, Florida

    Energy Technology Data Exchange (ETDEWEB)

    Oostrom, Martinus [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Vail, Lance W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-08-01

    Researchers at Pacific Northwest National Laboratory served as members of a U.S. Nuclear Regulatory Commission review team for the Florida Power & Light Company’s application for two combined construction permits and operating licenses (combined licenses or COLs) for two proposed new reactor units—Turkey Point Units 6 and 7. The review team evaluated the environmental impacts of the proposed action based on the October 29, 2014 revision of the COL application, including the Environmental Report, responses to requests for additional information, and supplemental information. As part of this effort, team members tasked with assessing the environmental effects of proposed construction and operation of Units 6 and 7 at the Turkey Point site reviewed two separate modeling studies that analyzed the interaction between surface water and groundwater that would be altered by the operation of radial collector wells (RCWs) at the site. To further confirm their understanding of the groundwater hydrodynamics and to consider whether certain actions, proposed after the two earlier modeling studies were completed, would alter the earlier conclusions documented by the review team in their draft environmental impact statement (EIS; NRC 2015), a third modeling analysis was performed. The third modeling analysis is discussed in this report.

  17. Sub-marine groundwater for the supply of drinking water. A review of the hydro-geological potential and its technical and economical feasibility.

    Science.gov (United States)

    Haakon Bakken, Tor; Mangset, Lars Erik

    2010-05-01

    assumptions as Zhou and Tol (2005), it is found that utilisation of sub-marine groundwater can be economically competitive. The calculation gives an expected unit cost of 1,23 US /m3. Performed Monte Carlo-simulations give 5 % and 95 % percentiles equal to the unit cost levels 1,07 and 1,39 US /m3, respectively. This is not far from the proposed feasibility benchmark of 1,14 US /m3 by Zhou and Tol (2005), or the average costs of 1,46 US /m3 derived from their large database of built desalination plants (based on reverse osmosis-technology). The dominating cost driver is considered being the salinity of the sub-marine groundwater, affecting the need for water treatment and consequently energy consumption. Hence it is concluded that a premise for the proposed technical concept is that the sub-marine groundwater holds sufficiently better quality (lower salinity) than the ambient sea water to justify the additional costs related to exploration and exploitation of the sub-marine water resource (i.e. the additional off-shore oil & gas technologies). A review of publications mainly from the US, supported by a limited number of publications originating from European research groups, were all positive in their conclusions that fresh and brackish water can be found on the continental shelf. These indications may therefore suggest that sub-marine groundwater may be a realistic alternative to desalination of sea water, seen from an economic point of view. Lower energy consumption related to treatment of less saline sub-marine groundwater moreover implies that environmental benefits, assuming the use of fossil fuels as energy source to water desalination, may be achieved.

  18. Groundwater and climate change research scoping study

    OpenAIRE

    Jackson, C. R.; Cheetham, M.; Guha, P

    2006-01-01

    This scoping study has reviewed much of the published literature in the field of climate change and groundwater research. Whilst it is not exhaustive with regard to groundwater quality issues, most of the published literature relating to climate change and groundwater resources, particularly in the UK, is covered. Further work is required to identify current research needs relating to the effects of climate change on groundwater quality. The study of the effects of climate chan...

  19. Road impacts on the Baca National Wildlife Refuge, Colorado, with emphasis on effects to surface- and shallow ground-water hydrology - A literature review

    Science.gov (United States)

    Andersen, Douglas C.

    2007-01-01

    A review of published research on unpaved road effects on surface-water and shallow ground-water hydrology was undertaken to assist the Baca National Wildlife Refuge, Colorado, in understanding factors potentially influencing refuge ecology. Few studies were found that addressed hydrological effects of roads on a comparable area of shallow slope in a semiarid region. No study dealt with road effects on surface- and ground-water supplies to ephemeral wetlands, which on the refuge are sustained by seasonal snowmelt in neighboring mountains. Road surfaces increase runoff, reduce infiltration, and serve as a sediment source. Roadbeds can interfere with normal surface- and ground-water flows and thereby influence the quantity, timing, and duration of water movement both across landscapes and through the soil. Hydrologic effects can be localized near the road as well as widespread and distant. The number, arrangement, and effectiveness of road-drainage structures (culverts and other devices) largely determine the level of hydrologic alteration produced by a road. Undesirable changes to natural hydrologic patterns can be minimized by considering potential impacts during road design, construction, and maintenance. Road removal as a means to restore desirable hydrologic conditions to landscapes adversely affected by roads has yet to be rigorously evaluated.

  20. Funded Social Security System: A Review of Issues in Four East Asian Countries Funded Social Security System: A Review of Issues in Four East Asian Countries

    Directory of Open Access Journals (Sweden)

    Frederick Ribe

    1994-03-01

    Full Text Available This paper reviews the structure and economic effects of the fullyfunded centralized public pension programs in several East Asian countries. The major weaknesses of these programs are variable and often inadequate replacement rates as well as poor population coverage. Aside from encouraging development of financial markets, their chief virtue is their avoidance of economic distortions associated with the alternative pay-as-you-go approach. Growth-modeling exercises surveyed in the paper suggest that such distortions are the main way in which social security affects aggregate welfare in the long run. The paper therefore argues that expected pay-as-you-go based reforms should involve introduction of minimal flatrate schemes as supplements to the existing systems. This paper reviews the structure and economic effects of the fullyfunded centralized public pension programs in several East Asian countries. The major weaknesses of these programs are variable and often inadequate replacement rates as well as poor population coverage. Aside from encouraging development of financial markets, their chief virtue is their avoidance of economic distortions associated with the alternative pay-as-you-go approach. Growth-modeling exercises surveyed in the paper suggest that such distortions are the main way in which social security affects aggregate welfare in the long run. The paper therefore argues that expected pay-as-you-go based reforms should involve introduction of minimal flatrate schemes as supplements to the existing systems.

  1. Review of Trace-Element Field-Blank Data Collected for the California Groundwater Ambient Monitoring and Assessment (GAMA) Program, May 2004-January 2008

    Science.gov (United States)

    Olsen, Lisa D.; Fram, Miranda S.; Belitz, Kenneth

    2010-01-01

    Trace-element quality-control samples (for example, source-solution blanks, field blanks, and field replicates) were collected as part of a statewide investigation of groundwater quality in California, known as the Priority Basins Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basins Project is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB) to assess and monitor the quality of groundwater resources used for drinking-water supply and to improve public knowledge of groundwater quality in California. Trace-element field blanks were collected to evaluate potential bias in the corresponding environmental data. Bias in the environmental data could result from contamination in the field during sample collection, from the groundwater coming into contact with contaminants on equipment surfaces or from other sources, or from processing, shipping, or analyzing the samples. Bias affects the interpretation of environmental data, particularly if any constituents are present solely as a result of extrinsic contamination that would have otherwise been absent from the groundwater that was sampled. Field blanks were collected, analyzed, and reviewed to identify and quantify extrinsic contamination bias. Data derived from source-solution blanks and laboratory quality-control samples also were considered in evaluating potential contamination bias. Eighty-six field-blank samples collected from May 2004 to January 2008 were analyzed for the concentrations of 25 trace elements. Results from these field blanks were used to interpret the data for the 816 samples of untreated groundwater collected over the same period. Constituents analyzed were aluminum (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), boron (B), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), lithium (Li), manganese (Mn), mercury (Hg), molybdenum

  2. Does the groundwater nitrate pollution in China pose a risk to human health? A critical review of published data.

    Science.gov (United States)

    Zhai, Yuanzheng; Lei, Yan; Wu, Jin; Teng, Yanguo; Wang, Jinsheng; Zhao, Xiaobing; Pan, Xiaodong

    2017-02-01

    Nitrate pollution has pervaded many parts of the world, especially in developing countries such as China. Based on the available groundwater nitrate data sets in China (2000-2015), the groundwater pollution levels at the provincial scale are evaluated which contains 33 provinces (units) except for Macau because of lacking data. Then, the potential risks posed to human health in national scale are quantified. In order to make the results more precise and systematical, both drinking and dermal contact exposure pathways are considered, and the influenced crowd are more finely divided into four groups to study the impacts of age and gender on the outcome, which include infants (0-6 months), children (7 months-17 years old), adult males (18 years old-), and adult females (18 years old-). Results indicate that there are seven units whose groundwater nitrate concentrations exceed the standard value with Shaanxi being a seriously poor condition. Facing the same level of nitrate, the health risk level changes in the order of infants > children > adult males > adult females. That is to say, minors and males are more vulnerable compared with adults and females, respectively. There is no adverse effect on adult females of the whole country, while gender really impacts on the health risk assessment result. Adult males, children, and infants face various degrees of health risk respectively in Shaanxi and Shandong, which are needed to pay more attention to.

  3. Degradation of nitrates with the participation of Fe(II) and Fe(0) in groundwater: A review

    Science.gov (United States)

    Vodyanitskii, Yu. N.; Mineev, V. G.

    2015-02-01

    Nitrates from soil and nitrogen fertilizers unused by plants become hazardous pollutants and contaminate surface and ground waters. In the water-saturated layers, into which nitrates are leached, the content of organic matter (i.e., electron donors necessary for nitrification) can be insufficient. The deficiency of electrons in the groundwater can be eliminated by Fe(II) minerals that remained in the heavy rocks and are available to microorganisms due to dispersion. However, when the groundwater table is shallow (less than at 10 m), the natural denitrification develops poorly; therefore, remediation is needed to enrich the contaminated water with electron donors. Zerovalent iron is most frequently used for this purpose. The efficiency of the Fe0 barriers for the purification of groundwater from nitrates increases due to the activation of anaerobic denitrifying bacteria. In addition, the geochemical conditions and the composition of the bacterial community change in the Fe0 barrier zone, which favors the development of a wide range of anaerobic hydrogenotrophic bacteria (primarily Fe(III) reductants).

  4. Professional Integration of Immigrant Teachers in the School System: A Literature Review

    Science.gov (United States)

    Niyubahwe, Aline; Mukamurera, Joséphine; Jutras, France

    2013-01-01

    This literature review article investigates the professional integration of teachers recently immigrated to Canada and other western countries. Its findings reveal a number of obstacles to the integration of immigrant teachers into the teaching profession. The review summarizes different initiatives facilitating or hampering immigrant teachers'…

  5. Professional Integration of Immigrant Teachers in the School System: A Literature Review

    Science.gov (United States)

    Niyubahwe, Aline; Mukamurera, Joséphine; Jutras, France

    2013-01-01

    This literature review article investigates the professional integration of teachers recently immigrated to Canada and other western countries. Its findings reveal a number of obstacles to the integration of immigrant teachers into the teaching profession. The review summarizes different initiatives facilitating or hampering immigrant…

  6. Groundwater Pollution and Vulnerability Assessment.

    Science.gov (United States)

    Kurwadkar, Sudarshan

    2017-10-01

    Groundwater is a critical resource that serve as a source of drinking water to large human population and, provide long-term water for irrigation purposes. In recent years; however, this precious resource being increasingly threatened, due to natural and anthropogenic activities. A variety of contaminants of emerging concern such as pharmaceuticals and personal care products, perfluorinated compounds, endocrine disruptors, and biological agents detected in the groundwater sources of both developing and developed nations. In this review paper, various studies have been included that documented instances of groundwater pollution and vulnerability to emerging contaminants of concern, pesticides, heavy metals, and leaching potential of various organic and inorganic contaminants from poorly managed residual waste products (biosolids, landfills, latrines, and septic tanks etc.). Understanding vulnerability of groundwater to pollution is critical to maintain the integrity of groundwater. A section on managed artificial recharge studies is included to highlight the sustainable approaches to groundwater conservation, replenishment and sustainability. This review paper is the synthesis of studies published in last one year that either documented the pollution problems or evaluated the vulnerability of groundwater pollution.

  7. groundwater contribution to crop water requirement groundwater ...

    African Journals Online (AJOL)

    eobe

    Keywords: Groundwater, water table, capillary rise, soil type, waterleaf, ... GROUNDWATER CONTRIBUTION TO WATERLEAF (TALINUM TRIANGULARE) IN OXISOLS, I. J. ... Nutritionally, ... information to facilitate increased crop production,.

  8. Impacts of climate change on rainfall extremes and urban drainage systems: A review

    DEFF Research Database (Denmark)

    Arnbjerg-Nielsen, Karsten; Willems, P.; Olsson, J.

    2013-01-01

    A review is made of current methods for assessing future changes in urban rainfall extremes and their effects on urban drainage systems, due to anthropogenic-induced climate change. The review concludes that in spite of significant advances there are still many limitations in our understanding of...... drainage infrastructure considering climate change impacts and co-optimizing these with other objectives will become ever more important to keep our cities habitable into the future. © IWA Publishing 2013....

  9. Review: Groundwater flow and transport modeling of karst aquifers, with particular reference to the North Coast Limestone aquifer system of Puerto Rico.

    Science.gov (United States)

    Ghasemizadeh, Reza; Hellweger, Ferdinand; Butscher, Christoph; Padilla, Ingrid; Vesper, Dorothy; Field, Malcolm; Alshawabkeh, Akram

    2012-12-01

    Karst systems have a high degree of heterogeneity and anisotropy, which makes them behave very differently from other aquifers. Slow seepage through the rock matrix and fast flow through conduits and fractures result in a high variation in spring response to precipitation events. Contaminant storage occurs in the rock matrix and epikarst, but contaminant transport occurs mostly along preferential pathways that are typically inaccessible locations, which makes modeling of karst systems challenging. Computer models for understanding and predicting hydraulics and contaminant transport in aquifers make assumptions about the distribution and hydraulic properties of geologic features that may not always apply to karst aquifers. This paper reviews the basic concepts, mathematical descriptions, and modeling approaches for karst systems. The North Coast Limestone aquifer system of Puerto Rico (USA) is introduced as a case study to illustrate and discuss the application of groundwater models in karst aquifer systems to evaluate aquifer contamination.

  10. Review: Groundwater flow and transport modeling of karst aquifers, with particular reference to the North Coast Limestone aquifer system of Puerto Rico

    Science.gov (United States)

    Ghasemizadeh, Reza; Hellweger, Ferdinand; Butscher, Christoph; Padilla, Ingrid; Vesper, Dorothy; Field, Malcolm; Alshawabkeh, Akram

    2013-01-01

    Karst systems have a high degree of heterogeneity and anisotropy, which makes them behave very differently from other aquifers. Slow seepage through the rock matrix and fast flow through conduits and fractures result in a high variation in spring response to precipitation events. Contaminant storage occurs in the rock matrix and epikarst, but contaminant transport occurs mostly along preferential pathways that are typically inaccessible locations, which makes modeling of karst systems challenging. Computer models for understanding and predicting hydraulics and contaminant transport in aquifers make assumptions about the distribution and hydraulic properties of geologic features that may not always apply to karst aquifers. This paper reviews the basic concepts, mathematical descriptions, and modeling approaches for karst systems. The North Coast Limestone aquifer system of Puerto Rico (USA) is introduced as a case study to illustrate and discuss the application of groundwater models in karst aquifer systems to evaluate aquifer contamination. PMID:23645996

  11. Stable mineral recrystallization in low temperature aqueous systems: A critical review

    Science.gov (United States)

    Gorski, Christopher A.; Fantle, Matthew S.

    2017-02-01

    Minerals may undergo recrystallization reactions in low temperature (chemistries on Earth. The reactions are also significant for modern environments, including engineered systems, as they imply that mineral lattices may be substantially more open to exchanging toxic elements and radionuclides with coexisting solutions than previously thought. To date, observations of stable mineral recrystallization are distributed among several disciplines, and no work has attempted to review their findings comprehensively. Accordingly, this review article presents laboratory evidence for stable mineral recrystallization, describes data collection and interpretation strategies, summarizes similar recrystallization systematics observed in multiple studies, explores the potential occurrence of stable mineral recrystallization in natural systems, and discusses possible mechanisms by which stable mineral recrystallization occurs. The review focuses primarily on carbonates, sulfates, and iron oxides because these minerals have been studied most extensively to date. The review concludes by presenting key questions that should be addressed in this field to further understand and account for stable mineral recrystallization in natural and engineered aqueous systems at low temperatures.

  12. Automated and electronically assisted hand hygiene monitoring systems: a systematic review.

    Science.gov (United States)

    Ward, Melissa A; Schweizer, Marin L; Polgreen, Philip M; Gupta, Kalpana; Reisinger, Heather S; Perencevich, Eli N

    2014-05-01

    Hand hygiene is one of the most effective ways to prevent transmission of health care-associated infections. Electronic systems and tools are being developed to enhance hand hygiene compliance monitoring. Our systematic review assesses the existing evidence surrounding the adoption and accuracy of automated systems or electronically enhanced direct observations and also reviews the effectiveness of such systems in health care settings. We systematically reviewed PubMed for articles published between January 1, 2000, and March 31, 2013, containing the terms hand AND hygiene or hand AND disinfection or handwashing. Resulting articles were reviewed to determine if an electronic system was used. We identified 42 articles for inclusion. Four types of systems were identified: electronically assisted/enhanced direct observation, video-monitored direct observation systems, electronic dispenser counters, and automated hand hygiene monitoring networks. Fewer than 20% of articles identified included calculations for efficiency or accuracy. Limited data are currently available to recommend adoption of specific automatic or electronically assisted hand hygiene surveillance systems. Future studies should be undertaken that assess the accuracy, effectiveness, and cost-effectiveness of such systems. Given the restricted clinical and infection prevention budgets of most facilities, cost-effectiveness analysis of specific systems will be required before these systems are widely adopted. Published by Mosby, Inc.

  13. Budgeting and Accounting in OECD Education Systems: A Literature Review. OECD Education Working Papers, No. 128

    Science.gov (United States)

    Fakharzadeh, Tala

    2016-01-01

    Recent demographic, economic and political trends have drawn attention to the issue of effectiveness and efficiency in the use of resources in the education sector. In the context of the renewed interest for the optimisation of resource use, this paper attempts to review the literature on budgeting and accounting in OECD education systems. The…

  14. Budgeting and Accounting in OECD Education Systems: A Literature Review. OECD Education Working Papers, No. 128

    Science.gov (United States)

    Fakharzadeh, Tala

    2016-01-01

    Recent demographic, economic and political trends have drawn attention to the issue of effectiveness and efficiency in the use of resources in the education sector. In the context of the renewed interest for the optimisation of resource use, this paper attempts to review the literature on budgeting and accounting in OECD education systems. The…

  15. Recent results on stability and response bounds of linear systems - a review

    DEFF Research Database (Denmark)

    Pommer, Christian; Kliem, Wolfhard

    2006-01-01

    of stability and response bounds of linear systems. In addition to reporting some interesting recent stability investigations, the basic concepts of stability are reviewed, and a short introduction to Lyapunov’s direct method is also presented. Particularly important for applications are response bounds...

  16. It Takes an Eco-System: A Review of the Research Administration Technology Landscape

    Science.gov (United States)

    Saas, Tyler; Kemp, James

    2017-01-01

    Deloitte Consulting LLP conducted a review of publicly available data sources with the goal of identifying the pre- and post-award systems used in higher education. The number and type of pre- and post-award systems identified not only show that higher education institutions (HEIs) use a variety of methods to facilitate research activities, but…

  17. High-resolution sonography of the peripheral nervous system - a review of the literature

    NARCIS (Netherlands)

    Beekman, R; Visser, LH

    2004-01-01

    High-resolution sonography is capable of depicting peripheral nerves and the brachial plexus. In this study we review the literature on this subject. Normal peripheral nerves have a characteristic echotexture. Most nerves are readily visualized, although this is not always the case with the nerves o

  18. Applications of magnetohydrodynamics in biological systems-a review on the numerical studies

    Science.gov (United States)

    Rashidi, Saman; Esfahani, Javad Abolfazli; Maskaniyan, Mahla

    2017-10-01

    Magnetohydrodynamic (MHD) fluid flow in different geometries relevant to human body parts is an interesting and important scientific area due to its applications in medical sciences. This article performs a comprehensive review on the applications of MHD and their numerical modelling in biological systems. Applications of MHD in medical sciences are classified into four categories in this paper. Applications of MHD in simple flow, peristaltic flow, pulsatile flow, and drag delivery are these categories. The numerical researches performed for these categories are reviewed and summarized separately. Finally, some conclusions and suggestions for future works based on the literature review are presented. The results indicated that during a surgery when it is necessary to drop blood flow or reduce tissue temperature, it may be achieved by using a magnetic field. Moreover, the review showed that the trapping is an important phenomenon in peristaltic flows that causes the formation of thrombus in blood and the movement of food bolus in gastrointestinal tract. This phenomenon may be disappeared by using a proper magnetic field. Finally, the concentration of particles that are delivered to the target region increases with an increase in the magnetic field intensity.

  19. Including Performance Assessments in Accountability Systems: A Review of Scale-Up Efforts

    Science.gov (United States)

    Tung, Rosann

    2010-01-01

    The purpose of this literature and field review is to understand previous efforts at scaling up performance assessments for use across districts and states. Performance assessments benefit students and teachers by providing more opportunities for students to demonstrate their knowledge and complex skills, by providing teachers with better…

  20. Cu Isotopic Composition in Surface Environments and in Biological Systems: A Critical Review

    Directory of Open Access Journals (Sweden)

    Zhuhong Wang

    2017-05-01

    Full Text Available Copper (Cu is a transition metal and an essential micronutrient for organisms, but also one of the most widespread toxic inorganic contaminants at very high content. The research on Cu isotopes has grown rapidly in the last decade. Hitherto, a large number of studies have been published on the theoretical fractionation mechanisms, experimental data and natural variations of Cu isotopes in variable environments and ecosystems. These studies reported a large variation of δ65Cu (−16.49 to +20.04‰ in terrestrial samples and showed that Cu isotopes could be fractionated by various biogeochemical processes to different extent. Several papers have previously reviewed the coupling of Cu and Zn isotope systematics, and we give here a tentative review of the recent publications only on Cu isotopesin variable surface repositories, animals and human beings, with a goal to attract much attention to research on Cu (and other metals behaviors in the environment and biological systems.

  1. Impact of chitosan composites and chitosan nanoparticle composites on various drug delivery systems: A review

    Directory of Open Access Journals (Sweden)

    M.Abd Elgadir

    2015-12-01

    Full Text Available Chitosan is a promising biopolymer for drug delivery systems. Because of its beneficial properties, chitosan is widely used in biomedical and pharmaceutical fields. In this review, we summarize the physicochemical and drug delivery properties of chitosan, selected studies on utilization of chitosan and chitosan-based nanoparticle composites in various drug delivery systems, and selected studies on the application of chitosan films in both drug delivery and wound healing. Chitosan is considered the most important polysaccharide for various drug delivery purposes because of its cationic character and primary amino groups, which are responsible for its many properties such as mucoadhesion, controlled drug release, transfection, in situ gelation, and efflux pump inhibitory properties and permeation enhancement. This review can enhance our understanding of drug delivery systems particularly in cases where chitosan drug-loaded nanoparticles are applied.

  2. Energy saving mechanisms, collective behavior and the variation range hypothesis in biological systems: A review

    CERN Document Server

    Trenchard, Hugh

    2016-01-01

    Energy saving mechanisms are ubiquitous in nature. Aerodynamic and hydrodynamic drafting, vortice uplift, Bernoulli suction, thermoregulatory coupling, path following, physical hooks, synchronization, and cooperation are only some of the better-known examples. While drafting mechanisms also appear in non-biological systems such as sedimentation and particle vortices, the broad spectrum of these mechanisms appears more diversely in biological systems including bacteria, spermatozoa, various aquatic species, birds, land animals, semi-fluid dwellers like turtle hatchlings, as well as human systems. We present the thermodynamic framework for energy saving mechanisms, and we review evidence in favor of the variation range hypothesis. This hypothesis posits that, as an evolutionary process, the variation range between strongest and weakest group members converges on the equivalent energy saving quantity that is generated by the energy saving mechanism. We also review self-organized structures that emerge due to ene...

  3. Impact of chitosan composites and chitosan nanoparticle composites on various drug delivery systems: A review

    OpenAIRE

    M. Abd Elgadir; Md.Salim Uddin; Sahena Ferdosh; Aishah Adam; Ahmed Jalal Khan Chowdhury; Md. Zaidul Islam Sarker

    2015-01-01

    Chitosan is a promising biopolymer for drug delivery systems. Because of its beneficial properties, chitosan is widely used in biomedical and pharmaceutical fields. In this review, we summarize the physicochemical and drug delivery properties of chitosan, selected studies on utilization of chitosan and chitosan-based nanoparticle composites in various drug delivery systems, and selected studies on the application of chitosan films in both drug delivery and wound healing. Chitosan is considere...

  4. Concepts and features about poka-yoke systems: a literature review

    OpenAIRE

    Gabriel Vidor; Tarcísio Abreu Saurin

    2011-01-01

    This paper has the purpose of analyzing methods, techniques and guidelines for the design, operation and maintenance of poka-yoke systems. In parallel it intends to contribute with concepts about what poka-yoke are and their classification. Therefore a literature review was made about systems poka-yoke concepts, poka-yoke systems classification, kinds of inspections, kinds of mistakes, the relationship between stability and statistical process control with mistake proofing systems, techniques...

  5. Laws for local energy systems. A review; Lagar foer lokala energisystem. En oeversikt

    Energy Technology Data Exchange (ETDEWEB)

    Bylund, S.I. [Bygginfo AB, Stockholm (Sweden); Moe, N.; Bjoerk, J. [Swedish National Board for Industrial and Technical Development (NUTEK), Stockholm (Sweden); Goethe, S.; Froste, H. [Swedish Environmental Protection Agency, Solna (Sweden); Larsen, B.; Gyberg, A. [Boverket, Karlskrona (Sweden)

    1996-10-01

    This report gives a popular descriptive orientation of existing laws regarding the establishment of small-scale energy technology, like wind power plants, heat pumps, solar heating and others, and also of more efficient power generation. In the first part of the report 11 different local energy systems are described, together with their environmental impact. The second part gives a review of more than 20 laws. The central content of the laws are described, not the complete text

  6. Clinical effects of air pollution on the central nervous system; a review.

    Science.gov (United States)

    Babadjouni, Robin M; Hodis, Drew M; Radwanski, Ryan; Durazo, Ramon; Patel, Arati; Liu, Qinghai; Mack, William J

    2017-09-01

    The purpose of this review is to describe recent clinical and epidemiological studies examining the adverse effects of urban air pollution on the central nervous system (CNS). Air pollution and particulate matter (PM) are associated with neuroinflammation and reactive oxygen species (ROS). These processes affect multiple CNS pathways. The conceptual framework of this review focuses on adverse effects of air pollution with respect to neurocognition, white matter disease, stroke, and carotid artery disease. Both children and older individuals exposed to air pollution exhibit signs of cognitive dysfunction. However, evidence on middle-aged cohorts is lacking. White matter injury secondary to air pollution exposure is a putative mechanism for neurocognitive decline. Air pollution is associated with exacerbations of neurodegenerative conditions such as Alzheimer's and Parkinson's diseases. Increases in stroke incidences and mortalities are seen in the setting of air pollution exposure and CNS pathology is robust. Large populations living in highly polluted environments are at risk. This review aims to outline current knowledge of air pollution exposure effects on neurological health. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Sports Injury Surveillance Systems: A Review of Methods and Data Quality.

    Science.gov (United States)

    Ekegren, Christina L; Gabbe, Belinda J; Finch, Caroline F

    2016-01-01

    Data from sports injury surveillance systems are a prerequisite to the development and evaluation of injury prevention strategies. This review aimed to identify ongoing sports injury surveillance systems and determine whether there are gaps in our understanding of injuries in certain sport settings. A secondary aim was to determine which of the included surveillance systems have evaluated the quality of their data, a key factor in determining their usefulness. A systematic search was carried out to identify (1) publications presenting methodological details of sports injury surveillance systems within clubs and organisations; and (2) publications describing quality evaluations and the quality of data from these systems. Data extracted included methodological details of the surveillance systems, methods used to evaluate data quality, and results of these evaluations. Following literature search and review, a total of 15 sports injury surveillance systems were identified. Data relevant to each aim were summarised descriptively. Most systems were found to exist within professional and elite sports. Publications concerning data quality were identified for seven (47%) systems. Validation of system data through comparison with alternate sources has been undertaken for only four systems (27%). This review identified a shortage of ongoing injury surveillance data from amateur and community sport settings and limited information about the quality of data in professional and elite settings. More surveillance systems are needed across a range of sport settings, as are standards for data quality reporting. These efforts will enable better monitoring of sports injury trends and the development of sports safety strategies.

  8. Life cycle assessment of aquaculture systems-a review of methodologies.

    Science.gov (United States)

    Henriksson, Patrik J G; Guinée, Jeroen B; Kleijn, René; de Snoo, Geert R

    As capture fishery production has reached its limits and global demand for aquatic products is still increasing, aquaculture has become the world's fastest growing animal production sector. In attempts to evaluate the environmental consequences of this rapid expansion, life cycle assessment (LCA) has become a frequently used method. The present review of current peer-reviewed literature focusing on LCA of aquaculture systems is intended to clarify the methodological choices made, identify possible data gaps, and provide recommendations for future development within this field of research. The results of this review will also serve as a start-up activity of the EU FP7 SEAT (Sustaining Ethical Aquaculture Trade) project, which aims to perform several LCA studies on aquaculture systems in Asia over the next few years. From a full analysis of methodology in LCA, six phases were identified to differ the most amongst ten peer-reviewed articles and two PhD theses (functional unit, system boundaries, data and data quality, allocation, impact assessment methods, interpretation methods). Each phase is discussed with regards to differences amongst the studies, current LCA literature followed by recommendations where appropriate. The conclusions and recommendations section reflects on aquaculture-specific scenarios as well as on some more general issues in LCA. Aquaculture LCAs often require large system boundaries, including fisheries, agriculture, and livestock production systems from around the globe. The reviewed studies offered limited coverage of production in developing countries, low-intensity farming practices, and non-finfish species, although most farmed aquatic products originate from a wide range of farming practices in Asia. Apart from different choices of functional unit, system boundaries and impact assessment methods, the studies also differed in their choice of allocation factors and data sourcing. Interpretation of results also differed amongst the studies

  9. Anterior cruciate ligament repair with LARS (ligament advanced reinforcement system: a systematic review

    Directory of Open Access Journals (Sweden)

    Machotka Zuzana

    2010-12-01

    Full Text Available Abstract Background Injury to the anterior cruciate ligament (ACL of the knee is common. Following complete rupture of the ACL, insufficient re-vascularization of the ligament prevents it from healing completely, creating a need for reconstruction. A variety of grafts are available for use in ACL reconstruction surgery, including synthetic grafts. Over the last two decades new types of synthetic ligaments have been developed. One of these synthetic ligaments, the Ligament Advanced Reinforcement System (LARS, has recently gained popularity. The aim of this systematic review was to assess the current best available evidence for the effectiveness of the LARS as a surgical option for symptomatic, anterior cruciate ligament rupture in terms of graft stability, rehabilitation time and return to pre-injury function. Method This systematic review included studies using subjects with symptomatic, ACL ruptures undergoing LARS reconstruction. A range of electronic databases were searched in May 2010. The methodological quality of studies was appraised with a modified version of the Law critical appraisal tool. Data relating to study characteristics, surgical times, complication rates, outcomes related to knee stability, quality of life, function, and return to sport as well as details of rehabilitation programs and timeframes were collected. Results This review identified four studies of various designs, of a moderate methodological quality. Only one case of knee synovitis was reported. Patient satisfaction with LARS was high. Graft stability outcomes were found to be inconsistent both at post operative and at follow up periods. The time frames of rehabilitation periods were poorly reported and at times omitted. Return to pre-injury function and activity was often discussed but not reported in results. Conclusions There is an emerging body of evidence for LARS with comparable complication rates to traditional surgical techniques, and high patient

  10. Building supply chain communication systems: a review of methods and techniques

    Directory of Open Access Journals (Sweden)

    A F Cutting-Decelle

    2006-06-01

    Full Text Available With the increasing importance of computer-based communication technologies, communication networks are becoming crucial in supply chain management. Given the objectives of the supply chain, supply chain management is situated at the intersection of different professional sectors, each of them with its own vocabulary, its own knowledge and rules. This paper provides a review of the main approaches to supply chain communications through the analysis of different ways of modelling a supply chain and the presentation of new semantic-based approaches that have been and are being developed to improve the quality of the information exchanges within the supply chain.

  11. Studies on Heavy Metal Pollution in Soil-Plant System: A Review

    Institute of Scientific and Technical Information of China (English)

    Wang Haiyan; Sun Xiangyang

    2003-01-01

    Heavy metal pollution in soil-plant system is of major environmental concern on a world scale and in China in par-ticular with the rapid development of industry. The heavy metal pollution status in soil-plant system in China, the research progresson the bioavailability of heavy metals (affecting factors, extraction methods, free-ion activity model, adsorption model, multivariateregression model, Q-I relationship, and compound pollution), and soil remediation are reviewed in the paper. Future research andmonitoring is also discussed.

  12. Allocatin of functions in man-machine systems: a perspective and literature review

    Energy Technology Data Exchange (ETDEWEB)

    Price, H. E.; Maisano, R. E.; Van Cott, H. P.

    1982-06-01

    This report reviews the literature relevant to allocation of functions and presents a procedure for the allocation process applicable to nuclear power plant control rooms. An historical perspective of man's relationship with technology is given as background. Methods and models that have been developed to aid the allocation process are then considered, followed by examples of real-world applications. The relationship of allocation of function to the system development process is outlined. The report then turns to the proposed procedure of the allocation process.

  13. Data mining for wearable sensors in health monitoring systems: a review of recent trends and challenges.

    Science.gov (United States)

    Banaee, Hadi; Ahmed, Mobyen Uddin; Loutfi, Amy

    2013-12-17

    The past few years have witnessed an increase in the development of wearable sensors for health monitoring systems. This increase has been due to several factors such as development in sensor technology as well as directed efforts on political and stakeholder levels to promote projects which address the need for providing new methods for care given increasing challenges with an aging population. An important aspect of study in such system is how the data is treated and processed. This paper provides a recent review of the latest methods and algorithms used to analyze data from wearable sensors used for physiological monitoring of vital signs in healthcare services. In particular, the paper outlines the more common data mining tasks that have been applied such as anomaly detection, prediction and decision making when considering in particular continuous time series measurements. Moreover, the paper further details the suitability of particular data mining and machine learning methods used to process the physiological data and provides an overview of the properties of the data sets used in experimental validation. Finally, based on this literature review, a number of key challenges have been outlined for data mining methods in health monitoring systems.

  14. Data Mining for Wearable Sensors in Health Monitoring Systems: A Review of Recent Trends and Challenges

    Directory of Open Access Journals (Sweden)

    Hadi Banaee

    2013-12-01

    Full Text Available The past few years have witnessed an increase in the development of wearable sensors for health monitoring systems. This increase has been due to several factors such as development in sensor technology as well as directed efforts on political and stakeholder levels to promote projects which address the need for providing new methods for care given increasing challenges with an aging population. An important aspect of study in such system is how the data is treated and processed. This paper provides a recent review of the latest methods and algorithms used to analyze data from wearable sensors used for physiological monitoring of vital signs in healthcare services. In particular, the paper outlines the more common data mining tasks that have been applied such as anomaly detection, prediction and decision making when considering in particular continuous time series measurements. Moreover, the paper further details the suitability of particular data mining and machine learning methods used to process the physiological data and provides an overview of the properties of the data sets used in experimental validation. Finally, based on this literature review, a number of key challenges have been outlined for data mining methods in health monitoring systems.

  15. Racial and ethnic disparities in the VA health care system: a systematic review.

    Science.gov (United States)

    Saha, Somnath; Freeman, Michele; Toure, Joahd; Tippens, Kimberly M; Weeks, Christine; Ibrahim, Said

    2008-05-01

    To better understand the causes of racial disparities in health care, we reviewed and synthesized existing evidence related to disparities in the "equal access" Veterans Affairs (VA) health care system. We systematically reviewed and synthesized evidence from studies comparing health care utilization and quality by race within the VA. Racial disparities in the VA exist across a wide range of clinical areas and service types. Disparities appear most prevalent for medication adherence and surgery and other invasive procedures, processes that are likely to be affected by the quantity and quality of patient-provider communication, shared decision making, and patient participation. Studies indicate a variety of likely root causes of disparities including: racial differences in patients' medical knowledge and information sources, trust and skepticism, levels of participation in health care interactions and decisions, and social support and resources; clinician judgment/bias; the racial/cultural milieu of health care settings; and differences in the quality of care at facilities attended by different racial groups. Existing evidence from the VA indicates several promising targets for interventions to reduce racial disparities in the quality of health care.

  16. Early social environment affects the endogenous oxytocin system: a review and future directions

    Directory of Open Access Journals (Sweden)

    Emily eAlves

    2015-03-01

    Full Text Available Endogenous oxytocin plays an important role in a wide range of human functions including birth, milk ejection during lactation and facilitation of social interaction. There is increasing evidence that both variations in the oxytocin receptor (OXTR and concentrations of oxytocin are associated with differences in these functions. The causes for the differences that have been observed in tonic and stimulated oxytocin release remain unclear. Previous reviews have suggested that across the life course, these differences may be due to individual factors, e.g. genetic variation (of the OXTR, age or sex, or be the result of early environmental influences such as social experiences, stress or trauma partly by inducing epigenetic changes. This review has three aims. First, we briefly discuss the endogenous oxytocin system, including physiology, development, individual differences and function. Secondly, current models describing the relationship between the early life environment and the development of the oxytocin system in humans and animals are discussed. Finally, we describe research designs that can be used to investigate the effects of the early environment on the oxytocin system, identifying specific areas of research that need further attention.

  17. Potential impacts from tephra fall to electric power systems: a review and mitigation strategies

    Science.gov (United States)

    Wardman, J. B.; Wilson, T. M.; Bodger, P. S.; Cole, J. W.; Stewart, C.

    2012-12-01

    Modern society is highly dependent on a reliable electricity supply. During explosive volcanic eruptions, tephra contamination of power networks (systems) can compromise the reliability of supply. Outages can have significant cascading impacts for other critical infrastructure sectors and for society as a whole. This paper summarises known impacts to power systems following tephra falls since 1980. The main impacts are (1) supply outages from insulator flashover caused by tephra contamination, (2) disruption of generation facilities, (3) controlled outages during tephra cleaning, (4) abrasion and corrosion of exposed equipment and (5) line (conductor) breakage due to tephra loading. Of these impacts, insulator flashover is the most common disruption. The review highlights multiple instances of electric power systems exhibiting tolerance to tephra falls, suggesting that failure thresholds exist and should be identified to avoid future unplanned interruptions. To address this need, we have produced a fragility function that quantifies the likelihood of insulator flashover at different thicknesses of tephra. Finally, based on our review of case studies, potential mitigation strategies are summarised. Specifically, avoiding tephra-induced insulator flashover by cleaning key facilities such as generation sites and transmission and distribution substations is of critical importance in maintaining the integrity of an electric power system.

  18. Removal of pharmaceuticals and personal care products in aquatic plant-based systems: a review.

    Science.gov (United States)

    Zhang, Dongqing; Gersberg, Richard M; Ng, Wun Jern; Tan, Soon Keat

    2014-01-01

    Pharmaceuticals and personal care products (PPCPs) in the aquatic environment are regarded as emerging contaminants and have attracted increasing concern. The use of aquatic plant-based systems such as constructed wetlands (CWs) for treatment of conventional pollutants has been well documented. However, available research studies on aquatic plant-based systems for PPCP removal are still limited. The removal of PPCPs in CWs often involves a diverse and complex set of physical, chemical and biological processes, which can be affected by the design and operational parameters selected for treatment. This review summarizes the PPCP removal performance in different aquatic plant-based systems. We also review the recent progress made towards a better understanding of the various mechanisms and pathways of PPCP attenuation during such phytoremediation. Additionally, the effect of key CW design characteristics and their interaction with the physico-chemical parameters that may influence the removal of PPCPs in functioning aquatic plant-based systems is discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Does Acupuncture Alter Pain-related Functional Connectivity of the Central Nervous System? A Systematic Review.

    Science.gov (United States)

    Villarreal Santiago, María; Tumilty, Steve; Mącznik, Aleksandra; Mani, Ramakrishnan

    2016-08-01

    Acupuncture has been studied for several decades to establish evidence-based clinical practice. This systematic review aims to evaluate evidence for the effectiveness of acupuncture in influencing the functional connectivity of the central nervous system in patients with musculoskeletal pain. A systematic search of the literature was conducted to identify studies in which the central response of acupuncture in patients with musculoskeletal pain was evaluated by neuroimaging techniques. Databases searched were AMED, CINAHL, Cochrane Library, EMBASE, MEDLINE, PEDro, Pubmed, SCOPUS, SPORTDiscuss, and Web of Science. Included studies were assessed by two independent reviewers for their methodological quality by using the Downs and Black questionnaire and for their levels of completeness and transparency in reporting acupuncture interventions by using Standards for Reporting Interventions in Clinical Trials of Acupuncture (STRICTA) criteria. Seven studies met the inclusion criteria. Three studies were randomized controlled trials (RCTs) and four studies were nonrandomized controlled trials (NRCTs). The neuroimaging techniques used were functional magnetic resonance imaging (fMRI) and positron emission tomography (PET). Positive effects on the functional connectivity of the central nervous system more consistently occurred during long-term acupuncture treatment. The results were heterogeneous from a descriptive perspective; however, the key findings support acupuncture's ability to alter pain-related functional connectivity in the central nervous system in patients with musculoskeletal pain.

  20. The effects of Crocus sativus (saffron and its constituents on nervous system: A review

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Khazdair

    2015-08-01

    Full Text Available Saffron or Crocus sativus L. (C. sativus has been widely used as a medicinal plant to promote human health, especially in Asia. The main components of saffron are crocin, picrocrocin and safranal. The median lethal doses (LD50 of C. sativus are 200 mg/ml and 20.7 g/kg in vitro and in animal studies, respectively. Saffron has been suggested to be effective in the treatment of a wide range of disorders including coronary artery diseases, hypertension, stomach disorders, dysmenorrhea and learning and memory impairments. In addition, different studies have indicated that saffron has anti-inflammatory, anti-atherosclerotic, antigenotoxic and cytotoxic activities. Antitussive effects of stigmas and petals of C. sativus and its components, safranal and crocin have also been demonstrated. The anticonvulsant and anti-Alzheimer properties of saffron extract were shown in human and animal studies. The efficacy of C. sativus in the treatment of mild to moderate depression was also reported in clinical trial. Administration of C. sativus and its constituents increased glutamate and dopamine levels in the brain in a dose-dependent manner. It also interacts with the opioid system to reduce withdrawal syndrome. Therefore, in the present article, the effects of C. sativus and its constituents on the nervous system and the possible underlying mechanisms are reviewed. Our literature review showed that C. sativus and its components can be considered as promising agents in the treatment of nervous system disorders.

  1. The effects of Crocus sativus (saffron) and its constituents on nervous system: A review.

    Science.gov (United States)

    Khazdair, Mohammad Reza; Boskabady, Mohammad Hossein; Hosseini, Mahmoud; Rezaee, Ramin; M Tsatsakis, Aristidis

    2015-01-01

    Saffron or Crocus sativus L. (C. sativus) has been widely used as a medicinal plant to promote human health, especially in Asia. The main components of saffron are crocin, picrocrocin and safranal. The median lethal doses (LD50) of C. sativus are 200 mg/ml and 20.7 g/kg in vitro and in animal studies, respectively. Saffron has been suggested to be effective in the treatment of a wide range of disorders including coronary artery diseases, hypertension, stomach disorders, dysmenorrhea and learning and memory impairments. In addition, different studies have indicated that saffron has anti-inflammatory, anti-atherosclerotic, antigenotoxic and cytotoxic activities. Antitussive effects of stigmas and petals of C. sativus and its components, safranal and crocin have also been demonstrated. The anticonvulsant and anti-Alzheimer properties of saffron extract were shown in human and animal studies. The efficacy of C. sativus in the treatment of mild to moderate depression was also reported in clinical trial. Administration of C. sativus and its constituents increased glutamate and dopamine levels in the brain in a dose-dependent manner. It also interacts with the opioid system to reduce withdrawal syndrome. Therefore, in the present article, the effects of C. sativus and its constituents on the nervous system and the possible underlying mechanisms are reviewed. Our literature review showed that C. sativus and its components can be considered as promising agents in the treatment of nervous system disorders.

  2. Soluble Microbial Products (SMPs Release in Activated Sludge Systems: a Review

    Directory of Open Access Journals (Sweden)

    Hamed Azami

    2012-12-01

    Full Text Available This review discusses the characterization, production and implications of soluble microbial products (SMPs in biological wastewater treatment. The precise definition of SMPs is open to talk about, but is currently regarded as “the pool of organic compounds that are released into solution from substrate metabolism and biomass decay”'.Some of the SMPs have been identified as humic acids, olysaccharides, proteins, amino acids, antibiotics,extracellular enzymes and structural components of cells and products of energy metabolism. They adversely affect the kinetic activity, flocculating and settling properties of sludge. This review outlines some important findings with regard to biodegradability and treatability of SMPs and also the effect of process parameters on their production.As SMPs are produced during biological treatment process, their trace amounts normally remain in the effluent that defines the highest COD removal efficiency. Their presence in effluent represents a high potential risk of toxic by-product formation during chlorine disinfection. Studies have indicated that among all wastewaterpost-treatment processes, the adsorption by granular activated carbon combined with biologically induced degradation is the most effective method for removal of SMPs. However, it may be concludes that the knowledge regarding SMPs is still under progress and more work is required to fully understand their contribution to the treatment process.

  3. Soluble microbial products (SMPs release in activated sludge systems: a review

    Directory of Open Access Journals (Sweden)

    Azami Hamed

    2012-12-01

    Full Text Available Abstract This review discusses the characterization, production and implications of soluble microbial products (SMPs in biological wastewater treatment. The precise definition of SMPs is open to talk about, but is currently regarded as “the pool of organic compounds that are released into solution from substrate metabolism and biomass decay”'. Some of the SMPs have been identified as humic acids, polysaccharides, proteins, amino acids, antibiotics, extracellular enzymes and structural components of cells and products of energy metabolism. They adversely affect the kinetic activity, flocculating and settling properties of sludge. This review outlines some important findings with regard to biodegradability and treatability of SMPs and also the effect of process parameters on their production. As SMPs are produced during biological treatment process, their trace amounts normally remain in the effluent that defines the highest COD removal efficiency. Their presence in effluent represents a high potential risk of toxic by-product formation during chlorine disinfection. Studies have indicated that among all wastewater post-treatment processes, the adsorption by granular activated carbon combined with biologically induced degradation is the most effective method for removal of SMPs. However, it may be concludes that the knowledge regarding SMPs is still under progress and more work is required to fully understand their contribution to the treatment process.

  4. Unintended Pregnancy and Its Adverse Social and Economic Consequences on Health System: A Narrative Review Article.

    Directory of Open Access Journals (Sweden)

    Mansureh Yazdkhasti

    2015-01-01

    Full Text Available Unintended pregnancy is among the most troubling public health problems and a major reproductive health issue worldwide imposing appreciable socioeconomic burden on individuals and society. Governments generally plan to control growth of births (especially wanted births as well as orphans and illegitimate births imposing extra burden on public funding of the governments which inevitably affects economic efficiency and leads to economic slowdown, too. The present narrative review focuses on socioeconomic impacts of unintended pregnancy from the health system perspective. Follow of Computerized searches of Academic, 53 scientific journals were found in various databases including PubMed, EMBASE, ISI, Iranian databases, IPPE, UNFPA (1985-2013. Original articles, review articles, published books about the purpose of the paper were used. During this search, 20 studies were found which met the inclusion criteria. Unintended pregnancy is one of the most critical challenges facing the public health system that imposes substantial financial and social costs on society. On the other hand, affecting fertility indicators, it causes reduced quality of life and workforce efficiency. Therefore lowering the incidence of intended pregnancies correlates with elevating economic growth, socio-economic development and promoting public health. Regarding recent policy changes in Iran on family planning programs and adopting a new approach in increasing population may place the country at a higher risk of increasing the rate of unintended pregnancy. Hence, all governmental plans and initiatives of public policy must be regulated intelligently and logically aiming to make saving in public spending and reduce healthcare cost inflation.

  5. Energy saving mechanisms, collective behavior and the variation range hypothesis in biological systems: A review.

    Science.gov (United States)

    Trenchard, Hugh; Perc, Matjaž

    2016-09-01

    Energy saving mechanisms are ubiquitous in nature. Aerodynamic and hydrodynamic drafting, vortice uplift, Bernoulli suction, thermoregulatory coupling, path following, physical hooks, synchronization, and cooperation are only some of the better-known examples. While drafting mechanisms also appear in non-biological systems such as sedimentation and particle vortices, the broad spectrum of these mechanisms appears more diversely in biological systems that include bacteria, spermatozoa, various aquatic species, birds, land animals, semi-fluid dwellers like turtle hatchlings, as well as human systems. We present the thermodynamic framework for energy saving mechanisms, and we review evidence in favor of the variation range hypothesis. This hypothesis posits that, as an evolutionary process, the variation range between strongest and weakest group members converges on the equivalent energy saving quantity that is generated by the energy saving mechanism. We also review self-organized structures that emerge due to energy saving mechanisms, including convective processes that can be observed in many systems over both short and long time scales, as well as high collective output processes in which a form of collective position locking occurs.

  6. Life cycle assessments of urban water systems: a comparative analysis of selected peer-reviewed literature.

    Science.gov (United States)

    Loubet, Philippe; Roux, Philippe; Loiseau, Eleonore; Bellon-Maurel, Veronique

    2014-12-15

    Water is a growing concern in cities, and its sustainable management is very complex. Life cycle assessment (LCA) has been increasingly used to assess the environmental impacts of water technologies during the last 20 years. This review aims at compiling all LCA papers related to water technologies, out of which 18 LCA studies deals with whole urban water systems (UWS). A focus is carried out on these 18 case studies which are analyzed according to criteria derived from the four phases of LCA international standards. The results show that whereas the case studies share a common goal, i.e., providing quantitative information to policy makers on the environmental impacts of urban water systems and their forecasting scenarios, they are based on different scopes, resulting in the selection of different functional units and system boundaries. A quantitative comparison of life cycle inventory and life cycle impact assessment data is provided, and the results are discussed. It shows the superiority of information offered by multi-criteria approaches for decision making compared to that derived from mono-criterion. From this review, recommendations on the way to conduct the environmental assessment of urban water systems are given, e.g., the need to provide consistent mass balances in terms of emissions and water flows. Remaining challenges for urban water system LCAs are identified, such as a better consideration of water users and resources and the inclusion of recent LCA developments (territorial approaches and water-related impacts).

  7. Data Mining for Wearable Sensors in Health Monitoring Systems: A Review of Recent Trends and Challenges

    Science.gov (United States)

    Banaee, Hadi; Ahmed, Mobyen Uddin; Loutfi, Amy

    2013-01-01

    The past few years have witnessed an increase in the development of wearable sensors for health monitoring systems. This increase has been due to several factors such as development in sensor technology as well as directed efforts on political and stakeholder levels to promote projects which address the need for providing new methods for care given increasing challenges with an aging population. An important aspect of study in such system is how the data is treated and processed. This paper provides a recent review of the latest methods and algorithms used to analyze data from wearable sensors used for physiological monitoring of vital signs in healthcare services. In particular, the paper outlines the more common data mining tasks that have been applied such as anomaly detection, prediction and decision making when considering in particular continuous time series measurements. Moreover, the paper further details the suitability of particular data mining and machine learning methods used to process the physiological data and provides an overview of the properties of the data sets used in experimental validation. Finally, based on this literature review, a number of key challenges have been outlined for data mining methods in health monitoring systems. PMID:24351646

  8. Groundwater Waters

    Directory of Open Access Journals (Sweden)

    Ramón Llamas

    1999-10-01

    Full Text Available The groundwaters released through springs constituted a basic element for the survival and progressive development of human beings. Man came to learn how to take better advantage of these waters by digging wells, irrigation channels, and galleries. Nevertheless, these activities do not require cooperation nor the collective agreement of relatively large groups of people, as in the case of creating the necessary structures to take advantage of the resources of surfacewaters. The construction and operation of these structures was a powerful factor in the birth of an urban or civil society – the designated water civilizations. The difference between people taking advantage of groundwater, quasi-individually, and those of surface water, where people work in a group, has continued to the present day. Whereas earlier, this difference did not bring about any special problems, the technological advances of this century, especially theturbine pump, have led to a spectacular increase in the use of roundwater. This advance has significantly contributed to reducing hunger in the world and has provided potable water in developing countries. However, the almost generalized lack of planning and control in the exploitation of these groundwaters reflects that they are little or badly understood by the managers of water policy in almost every country. As such, problems have occurred which have often become exaggerated, giving rise to water-myths. These problems, though, should be addressed if the aim is the sustainable usage of surface water as well as groundwater. To counter any misconceptions and to seek solutions to the problems, distinct plans of action can be highlighted: educating the public; fomenting a system of participative management and decisive support for the communities of users of subterranean waters; integrating a sufficient number of experts in hydrology in the various water management organizations;and assuring transparency of the data on

  9. Assessing Hospital Physicians' Acceptance of Clinical Information Systems: A Review of the Relevant Literature

    Directory of Open Access Journals (Sweden)

    Bram Pynoo

    2013-06-01

    Full Text Available In view of the tremendous potential benefits of clinical information systems (CIS for the quality of patient care; it is hard to understand why not every CIS is embraced by its targeted users, the physicians. The aim of this study is to propose a framework for assessing hospital physicians' CIS-acceptance that can serve as a guidance for future research into this area. Hereto, a review of the relevant literature was performed in the ISI Web-of-Science database. Eleven studies were withheld from an initial dataset of 797 articles. Results show that just as in business settings, there are four core groups of variables that influence physicians' acceptance of a CIS: its usefulness and ease of use, social norms, and factors in the working environment that facilitate use of the CIS (such as providing computers/workstations, compatibility between the new and existing system.... We also identified some additional variables as predictors of CIS-acceptance.

  10. The effects of operational and environmental variations on anaerobic wastewater treatment systems: a review

    Energy Technology Data Exchange (ETDEWEB)

    Leitao, R.C. [Embrapa Agroindustria Tropical (Brazilian Agricultural Research Corporation, Inst. of Tropical Agroindustry), Fortaleza (Brazil); Haandel, A.C. van [Federal University of Campina Grande (Brazil); Zeeman, G.; Lettinga, G. [Wageningen Univ. (Netherlands)

    2006-06-15

    With the aim of improving knowledge about the stability and reliability of anaerobic wastewater treatment systems, several researchers have studied the effects of operational or environmental variations on the performance of such reactors. In general, anaerobic reactors are affected by changes in external factors, but the severity of the effect is dependent upon the type, magnitude, duration and frequency of the imposed changes. The typical responses include a decrease in performance, accumulation of volatile fatty acids, drop in pH and alkalinity, change in biogas production and composition, and sludge washout. This review summarises the causes, types and effects of operational and environmental variation on anaerobic wastewater treatment systems. However, there still remain some unclear technical and scientific aspects that are necessary for the improvement of the stability and reliability of anaerobic processes. (author)

  11. Evolution of autonomous and semi-autonomous robotic surgical systems: a review of the literature.

    Science.gov (United States)

    Moustris, G P; Hiridis, S C; Deliparaschos, K M; Konstantinidis, K M

    2011-12-01

    Autonomous control of surgical robotic platforms may offer enhancements such as higher precision, intelligent manoeuvres, tissue-damage avoidance, etc. Autonomous robotic systems in surgery are largely at the experimental level. However, they have also reached clinical application. A literature review pertaining to commercial medical systems which incorporate autonomous and semi-autonomous features, as well as experimental work involving automation of various surgical procedures, is presented. Results are drawn from major databases, excluding papers not experimentally implemented on real robots. Our search yielded several experimental and clinical applications, describing progress in autonomous surgical manoeuvres, ultrasound guidance, optical coherence tomography guidance, cochlear implantation, motion compensation, orthopaedic, neurological and radiosurgery robots. Autonomous and semi-autonomous systems are beginning to emerge in various interventions, automating important steps of the operation. These systems are expected to become standard modality and revolutionize the face of surgery. Copyright © 2011 John Wiley & Sons, Ltd.

  12. Concepts and features about poka-yoke systems: a literature review

    Directory of Open Access Journals (Sweden)

    Gabriel Vidor

    2011-05-01

    Full Text Available This paper has the purpose of analyzing methods, techniques and guidelines for the design, operation and maintenance of poka-yoke systems. In parallel it intends to contribute with concepts about what poka-yoke are and their classification. Therefore a literature review was made about systems poka-yoke concepts, poka-yoke systems classification, kinds of inspections, kinds of mistakes, the relationship between stability and statistical process control with mistake proofing systems, techniques and directions to design and manage poka-yoke. An analysis was carried out with each subject relating poka-yoke with the subject. At the end the absence of a poka-yoke management system was evident, because techniques for design, operation and maintenance aren’t consistent.

  13. THE USE OF CHRONOTHERAPEUTICS IN DESIGN OF PULSATILE DELIVERY SYSTEMS- A REVIEW

    Directory of Open Access Journals (Sweden)

    D’Souza A

    2012-04-01

    Full Text Available Many therapeutic agents are most effective when made available at constant rates, near the absorption sites or at correct time of administration. Recently a greater effort has been taken in designing delivery systems which synchronize drug delivery with circadian rhythms in order to optimize efficacy and /or minimize side effects. Pulsatile systems deliver the drug at right site of action at the right time and in the right amount. Chronotherapeutics is the discipline concerned with the delivery of drugs according to inherent activities of a disease over a certain period of time. Chronotherapy can particularly benefit patients suffering from allergic rhinitis, rheumatoid arthritis and related disorders, asthma, cancer, cardiovascular diseases, and peptic ulcer disease. This review gives an outline as to how pulsatile drug delivery systems based on circadian rhythms are developed.

  14. [Pain assessment using the Facial Action Coding System. A systematic review].

    Science.gov (United States)

    Rojo, Rosa; Prados-Frutos, Juan Carlos; López-Valverde, Antonio

    2015-10-21

    Self-reporting is the most widely used pain measurement tool, although it may not be useful in patients with loss or deficit in communication skills. The aim of this paper was to undertake a systematic review of the literature of pain assessment through the Facial Action Coding System (FACS). The initial search found 4,335 references and, within the restriction «FACS», these were reduced to 40 (after exclusion of duplicates). Finally, only 26 articles meeting the inclusion criteria were included. Methodological quality was assessed using the GRADE system. Most patients were adults and elderly health conditions, or cognitive deficits and/or chronic pain. Our conclusion is that FACS is a reliable and objective tool in the detection and quantification of pain in all patients.

  15. Environmental management and organisation systems. A critical review; Umweltmanagement- und Organisationssysteme. Eine kritische Durchleuchtung

    Energy Technology Data Exchange (ETDEWEB)

    Schottelius, D. [Anwaltssozietaet Hoffmann, Liebs, Fritsch und Partner, Frankfurt am Main (Germany); Kuepper-Djindjic, C. [Anwaltssozietaet Hoffmann, Liebs, Fritsch und Partner, Frankfurt am Main (Germany)

    1994-11-20

    The FRG is amongst the industrial nations with the tightest, in parts hardly comprehensible network of regulative provisions by laws, statutory orders, administrative regulations as well as technical rules and standards included in the legal system. With regard to the establishment of management and organisation systems until now there are only few statutory provisions in Germany. The article is to critically review developments and to show connections and interactions between property and procedure provisions. (orig.) [Deutsch] Die Bundesrepublik Deutschland gehoert zu den Industrielaendern mit dem dichtesten, in seinen Teilbereichen kaum noch ueber- und durchschaubaren Netz ordnungsrechtlicher Vorgaben durch Gesetze, Rechtsverordnungen, Verwaltungsvorschriften und ins Rechtssystem einbezogene technische Normen und Regelwerken. Hinsichtlich der Einrichtung von Management- und Organisationssystemen hat Deutschland bisher weitgehend auf gesetzliche Vorgaben verzichtet. Der Beitrag soll Entwicklungen kritisch beleuchten sowie Zusammenhaenge und Zusammenwirken zwischen Sach- und Verfahrensvorschriften aufzeigen. (orig.)

  16. Suicidal Ideation and Behavior in Youth in the Juvenile Justice System: A Review of the Literature.

    Science.gov (United States)

    Stokes, Marquita L; McCoy, Kathleen P; Abram, Karen M; Byck, Gayle R; Teplin, Linda A

    2015-07-01

    Suicide is prevalent among youth, especially those involved in the juvenile justice system. Although many studies have examined suicidal ideation and behavior in delinquent youth, prevalence rates vary widely. This article reviews studies of suicidal ideation and behavior in youth in the juvenile justice system, focusing on the point of contact: incarceration status and stage of judicial processing. Suicidal ideation and behavior are prevalent and increase with greater involvement in the juvenile justice system. Depression, sexual abuse, and trauma were the most commonly identified predictors of suicidal ideation and behavior. Prevalence rates of suicidal ideation and behavior vary by gender and race/ethnicity, indicating the need for gender-specific and culturally relevant interventions.

  17. Efficient thermal desalination technologies with renewable energy systems: A state-of-the-art review

    Energy Technology Data Exchange (ETDEWEB)

    Esfahani, Iman Janghorban; Rashidi, Jouan; Ifaei, Pouya; Yoo, ChangKyoo [Center for Environmental Studies, Kyung Hee University, Yongin (Korea, Republic of)

    2016-02-15

    Due to the current fossil fuel crisis and associated adverse environmental impacts, renewable energy sources (RES) have drawn interest as alternatives to fossil fuels for powering water desalination systems. Over the last few decades the utility of renewable energy sources such as solar, geothermal, and wind to run desalination processes has been explored. However, the expansion of these technologies to larger scales is hampered by techno-economic and thermo-economic challenges. This paper reviews the state-of-the-art in the field of renewable energy-powered thermal desalination systems (RE-PTD) to compare their productivity and efficiency through thermodynamic, economic, and environmental analyses. We performed a comparative study using published data to classify RE-PTD systems technologies on the basis of the energy collection systems that they use. Among RE-PTD systems, solar energy powered-thermal desalination systems demonstrate high thermo-environ-economic efficiency to produce fresh water to meet various scales of demand.

  18. [Initiation and inhibition of free-radical processes in biochemical peroxidase systems: a review].

    Science.gov (United States)

    Metelitsa, D I; Karaseva, E I

    2007-01-01

    The role of complexes containing oxygen or peroxide in monooxygenase systems and models thereof, as well as in peroxidase- and quasi-peroxidase-catalyzed processes, has been reviewed. Pathways of conversion of these intermediate complexes involving single-electron (radical) and two-electron (heterolytic) mechanisms are dealt with. Coupled peroxidase-catalyzed oxidation of aromatic amines and phenols is analyzed; inhibition and activation of peroxidase-catalyzed reactions are characterized quantitatively. Oxidation of chromogenic substrates (ABTS, OPD, and TMB) in the presence of phenolic inhibitors or polydisulfides of substituted phenols is characterized by inhibition constants (Ki, micromol). Activation of peroxidase-catalyzed oxidation of the same substrates is characterized by the degree (coefficient) of activation (alpha, M(-1)), which was determined for 2-aminothiazole, melamine, tetrazole, and its 5-substituted derivatives. Examples of applied use of peroxidase-catalyzed enzyme and model systems are given (oxidation of organic compounds, chemical analysis, enzyme immunoassay, tests for antioxidant activity of biological fluids).

  19. Moon formation and orbital evolution in extrasolar planetary systems - A literature review

    Directory of Open Access Journals (Sweden)

    Lewis K.

    2011-02-01

    Full Text Available With over 450 extrasolar planets detected, the possibility of searching for moons of these planets is starting to be investigated. In order to make efficient use of limited observing resources, it would be useful if the types of moons that a given planet is likely to host was known prior to detection. Fortunately, informed by simulations of moon formation in our own solar system, as well as more general theoretical investigations of moon orbital evolution, such information is now available. I present a review of literature results concerning the likely physical and orbital properties of extra-solar moons, and how these properties are predicted to vary with the properties of their host planet.

  20. Sucrose esters as natural surfactants in drug delivery systems--a mini-review.

    Science.gov (United States)

    Szűts, Angéla; Szabó-Révész, Piroska

    2012-08-20

    Sucrose esters (SEs) are widely used in the food and cosmetic industries and there has recently been great interest in their applicability in different pharmaceutical fields. They are natural and biodegradable excipients with well-known emulsifying and solubilizing behavior. Currently the most common pharmaceutical applications of SEs are for the enhancement of drug dissolution and drug absorption/permeation, and in controlled-release systems. Although the number of articles on SEs is continuously increasing, they have not yet been widely used in the pharmaceutical industry. The aim of this review is to discuss and summarize some of the findings and applications of SEs in different areas of drug delivery. The article highlights the main properties of SEs and focuses on their use in pharmaceutical technology and on their regulatory and toxicological status. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Zebrafish housing systems: a review of basic operating principles and considerations for design and functionality.

    Science.gov (United States)

    Lawrence, Christian; Mason, Timothy

    2012-01-01

    The strategies for housing zebrafish used in biomedical research have evolved considerably over the past three decades. To keep pace with the rapid expansion and development of the zebrafish model system, the field has generally moved from keeping fish at the level of aquarium hobbyist to that of industrialized, recirculating aquaculture. Numerous commercial system vendors now offer increasingly sophisticated housing systems based on design principles that maximize the number of animals that can be housed in a given space footprint, and they are thus able to support large and diverse research programs. This review is designed to provide managers, lab animal veterinarians, investigators, and other parties responsible for care and use of these animals with a comprehensive overview of the basic operating and design principles of zebrafish housing systems. This information can be used to help plan the construction of new facilities and/or the upgrade and maintenance of existing operations.

  2. Intraoperative awareness in a regional medical system: a review of 3 years' data.

    Science.gov (United States)

    Pollard, Richard J; Coyle, Joseph P; Gilbert, Richard L; Beck, Janet E

    2007-02-01

    Intraoperative awareness in patients undergoing general anesthesia is an infrequent but well-described adverse outcome. The reported incidence of this phenomenon is between 0.1% and 0.9%. With institutional review board approval, the authors reviewed continuous quality improvement data from 3 yr (2002-2004) at the locations where the physician group provided anesthesia. Board-certified anesthesiologists supervising certified registered nurse anesthetists in the anesthesia care team model of practice delivered all anesthetics. Brain function monitors were not used in the operating room setting. Patients were interviewed twice during a 48-h postoperative period and, as part of that process, underwent a modified Brice interview to determine intraoperative awareness. All cases that met the criteria for awareness were examined by the continuous quality improvement committee to modify anesthetic practice and were included in this study. Data from 211,842 patients undergoing anesthesia were considered. Of these, the continuous quality improvement process followed up 177,468 (83.1%). Cases were not included in the study if the patient was younger than 18 yr, did not have a general anesthetic, or had a terminal event during the hospital course. By these criteria, a total of 87,361 patients followed by the continuous quality improvement process were at risk for awareness. Six patients reported instances of recall. The incidence of intraoperative awareness in this large sample of patients from a regional medical center undergoing general anesthesia was 0.0068%, or 1 per 14,560 patients, substantially less than that reported in the recent literature.

  3. Length scales in glass-forming liquids and related systems: a review

    Science.gov (United States)

    Karmakar, Smarajit; Dasgupta, Chandan; Sastry, Srikanth

    2016-01-01

    The central problem in the study of glass-forming liquids and other glassy systems is the understanding of the complex structural relaxation and rapid growth of relaxation times seen on approaching the glass transition. A central conceptual question is whether one can identify one or more growing length scale(s) associated with this behavior. Given the diversity of molecular glass-formers and a vast body of experimental, computational and theoretical work addressing glassy behavior, a number of ideas and observations pertaining to growing length scales have been presented over the past few decades, but there is as yet no consensus view on this question. In this review, we will summarize the salient results and the state of our understanding of length scales associated with dynamical slow down. After a review of slow dynamics and the glass transition, pertinent theories of the glass transition will be summarized and a survey of ideas relating to length scales in glassy systems will be presented. A number of studies have focused on the emergence of preferred packing arrangements and discussed their role in glassy dynamics. More recently, a central object of attention has been the study of spatially correlated, heterogeneous dynamics and the associated length scale, studied in computer simulations and theoretical analysis such as inhomogeneous mode coupling theory. A number of static length scales have been proposed and studied recently, such as the mosaic length scale discussed in the random first-order transition theory and the related point-to-set correlation length. We will discuss these, elaborating on key results, along with a critical appraisal of the state of the art. Finally we will discuss length scales in driven soft matter, granular fluids and amorphous solids, and give a brief description of length scales in aging systems. Possible relations of these length scales with those in glass-forming liquids will be discussed.

  4. Environmental dynamics of metal oxide nanoparticles in heterogeneous systems: A review

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Sung Hee, E-mail: s.joo1@miami.edu [Department of Civil, Architectural, and Environmental Engineering, University of Miami, 1251 Memorial Dr. McArthur Engineering Building, Coral Gables, FL 33146-0630 (United States); Zhao, Dongye [Department of Civil and Environmental Engineering, 238 Harbert Engineering Center, Auburn University, Auburn, AL 36849 (United States)

    2017-01-15

    Highlights: • Influence of contaminants on the mobility of metal oxide nanoparticles (MNPs). • Synergistic effects of MNPs in the presence of contaminants. • Effect of environmental factors on the transformed MNPs. • Research direction on the toxicity modeling assessment of heterogeneous systems. - Abstract: Metal oxide nanoparticles (MNPs) have been used for many purposes including water treatment, health, cosmetics, electronics, food packaging, and even food products. As their applications continue to expand, concerns have been mounting about the environmental fate and potential health risks of the nanoparticles in the environment. Based on the latest information, this review provides an overview of the factors that affect the fate, transformation and toxicity of MNPs. Emphasis is placed on the effects of various aquatic contaminants under various environmental conditions on the transformation of metal oxides and their transport kinetics – both in homogeneous and heterogeneous systems – and the effects of contaminants on the toxicity of MNPs. The presence of existing contaminants decreases bioavailability through hetero-aggregation, sorption, and/or complexation upon an interaction with MNPs. Contaminants also influence the fate and transport of MNPs and exhibit their synergistic toxic effects that contribute to the extent of the toxicity. This review will help regulators, engineers, and scientists in this field to understand the latest development on MNPs, their interactions with aquatic contaminants as well as the environmental dynamics of their fate and transformation. The knowledge gap and future research needs are also identified, and the challenges in assessing the environmental fate and transport of nanoparticles in heterogeneous systems are discussed.

  5. Conversion of native terrestrial ecosystems in Hawai‘i to novel grazing systems: a review

    Science.gov (United States)

    Leopold, Christina R.; Hess, Steven C.

    2017-01-01

    The remote oceanic islands of Hawai‘i exemplify the transformative effects that non-native herbivorous mammals can bring to isolated terrestrial ecosystems. We reviewed published literature containing systematically collected, analyzed, and peer-reviewed original data specifically addressing direct effects of non-native hoofed mammals (ungulates) on terrestrial ecosystems, and indirect effects and interactions on ecosystem processes in Hawai‘i. The effects of ungulates on native vegetation and ecosystems were addressed in 58 original studies and mostly showed strong short-term regeneration of dominant native trees and understory ferns after ungulate removal, but unassisted recovery was dependent on the extent of previous degradation. Ungulates were associated with herbivory, bark-stripping, disturbance by hoof action, soil erosion, enhanced nutrient cycling from the interaction of herbivory and grasses, and increased pyrogenicity and competition between native plants and pasture grasses. No studies demonstrated that ungulates benefitted native ecosystems except in short-term fire-risk reduction. However, non-native plants became problematic and continued to proliferate after release from herbivory, including at least 11 species of non-native pasture grasses that had become established prior to ungulate removal. Competition from non-native grasses inhibited native species regeneration where degradation was extensive. These processes have created novel grazing systems which, in some cases, have irreversibly altered Hawaii’s terrestrial ecology. Non-native plant control and outplanting of rarer native species will be necessary for recovery where degradation has been extensive. Lack of unassisted recovery in some locations should not be construed as a reason to not attempt restoration of other ecosystems.

  6. Application of organic petrography in North American shale petroleum systems: A review

    Science.gov (United States)

    Hackley, Paul C.; Cardott, Brian J.

    2016-01-01

    Organic petrography via incident light microscopy has broad application to shale petroleum systems, including delineation of thermal maturity windows and determination of organo-facies. Incident light microscopy allows practitioners the ability to identify various types of organic components and demonstrates that solid bitumen is the dominant organic matter occurring in shale plays of peak oil and gas window thermal maturity, whereas oil-prone Type I/II kerogens have converted to hydrocarbons and are not present. High magnification SEM observation of an interconnected organic porosity occurring in the solid bitumen of thermally mature shale reservoirs has enabled major advances in our understanding of hydrocarbon migration and storage in shale, but suffers from inability to confirm the type of organic matter present. Herein we review organic petrography applications in the North American shale plays through discussion of incident light photographic examples. In the first part of the manuscript we provide basic practical information on the measurement of organic reflectance and outline fluorescence microscopy and other petrographic approaches to the determination of thermal maturity. In the second half of the paper we discuss applications of organic petrography and SEM in all of the major shale petroleum systems in North America including tight oil plays such as the Bakken, Eagle Ford and Niobrara, and shale gas and condensate plays including the Barnett, Duvernay, Haynesville-Bossier, Marcellus, Utica, and Woodford, among others. Our review suggests systematic research employing correlative high resolution imaging techniques and in situ geochemical probing is needed to better document hydrocarbon storage, migration and wettability properties of solid bitumen at the pressure and temperature conditions of shale reservoirs.

  7. Remedies proposed for China's groundwater problems

    Science.gov (United States)

    Loaiciga, Hugo A.

    Groundwater experts and hydrologists from China and 10 other nations recently gathered in Beijing to exchange state-of-the-art scientific and technological knowledge on groundwater hydrology, modeling, remediation, and management. The participants also reviewed groundwater environmental conditions in China, identified key problems, and made recommendations to help guide the nation's groundwater policy.The Regional Workshop on Ground Water Contamination, held from July 31 to August 4, 1995, was the fifth of a series of regional workshops sponsored by the Scientific Committee on Problems of the Environment of the United Nations Environmental Program. Earlier workshops were held in Thailand (1991), Costa Rica (1993), the Czech Republic (1994), and Australia (1994).

  8. Impacts of Groundwater Pumping on Regional and Global Water Resources

    Science.gov (United States)

    Wada, Yoshihide

    2016-01-01

    Except frozen water in ice and glaciers (68%), groundwater is the world's largest distributed store of freshwater (30%), and has strategic importance to global food and water security. In this chapter, the most recent advances assessing human impact on regional and global groundwater resources are reviewed. This chapter critically evaluates the recently advanced modeling approaches quantifying the effect of groundwater pumping in regional and global groundwater resources and the evidence of feedback to the Earth system including sea-level rise associated with groundwater use. At last, critical challenges and opportunities are identified in the use of groundwater to adapt to growing food demand and uncertain climate.

  9. Effects of Fuel and Nozzle Characteristics on Micro Gas Turbine System: A Review

    Science.gov (United States)

    Akasha Hashim, Muhammad; Khalid, Amir; Salleh, Hamidon; Sunar, Norshuhaila Mohamed

    2017-08-01

    For many decades, gas turbines have been used widely in the internal combustion engine industry. Due to the deficiency of fossil fuel and the concern of global warming, the used of bio-gas have been recognized as one of most clean fuels in the application of engine to improve performance of lean combustion and minimize the production of NOX and PM. This review paper is to understand the combustion performance using dual-fuel nozzle for a micro gas turbine that was basically designed as a natural gas fuelled engine, the nozzle characteristics of the micro gas turbine has been modelled and the effect of multi-fuel used were investigated. The used of biogas (hydrogen) as substitute for liquid fuel (methane) at constant fuel injection velocity, the flame temperature is increased, but the fuel low rate reduced. Applying the blended fuel at constant fuel rate will increased the flame temperature as the hydrogen percentages increased. Micro gas turbines which shows the uniformity of the flow distribution that can be improved without the increase of the pressure drop by applying the variable nozzle diameters into the fuel supply nozzle design. It also identifies the combustion efficiency, better fuel mixing in combustion chamber using duel fuel nozzle with the largest potential for the future. This paper can also be used as a reference source that summarizes the research and development activities on micro gas turbines.

  10. An introduction to fast dissolving oral thin film drug delivery systems: a review.

    Science.gov (United States)

    Kathpalia, Harsha; Gupte, Aasavari

    2013-12-01

    Many pharmaceutical companies are switching their products from tablets to fast dissolving oral thin films (OTFs). Films have all the advantages of tablets (precise dosage, easy administration) and those of liquid dosage forms (easy swallowing, rapid bioavailability). Statistics have shown that four out of five patients prefer orally disintegrating dosage forms over conventional solid oral dosages forms. Pediatric, geriatric, bedridden, emetic patients and those with Central Nervous System disorders, have difficulty in swallowing or chewing solid dosage forms. Many of these patients are non-compliant in administering solid dosage forms due to fear of choking. OTFs when placed on the tip or the floor of the tongue are instantly wet by saliva. As a result, OTFs rapidly hydrate and then disintegrate and/or dissolve to release the medication for local and/or systemic absorption. This technology provides a good platform for patent non- infringing product development and for increasing the patent life-cycle of the existing products. The application of fast dissolving oral thin films is not only limited to buccal fast dissolving system, but also expands to other applications like gastroretentive, sublingual delivery systems. This review highlights the composition including the details of various types of polymers both natural and synthetic, the different types of manufacturing techniques, packaging materials and evaluation tests for the OTFs.

  11. A Review: Transdermal Drug Delivery System: A Tool For Novel Drug Delivery System

    Directory of Open Access Journals (Sweden)

    NIKHIL SHARMA

    2011-06-01

    Full Text Available The human skin is a readily accessible surface for drug delivery. Skin of an average adult body covers a surface of approximately 2 m2 and receives about one-third of the blood circulating through the body. Over the past decades, developing controlled drug delivery has become increasingly important in the pharmaceutical industry. The human skin surface is known to contain, on an average, 10- 70 hair follicles and 200-250 sweat ducts on every square centimeters of the skin area. It is one of the most readily accessible organs of the human body. There is considerable interest in the skin as a site of drug application both for local and systemic effect. However, the skin, in particular the stratum corneum, poses a formidable barrier to drug penetration thereby limiting topical and transdermal bioavailability. Skin penetration enhancement techniques have been developed to improve bioavailability and increase the range of drugs for which topical and transdermal delivery is a viable option. During the past decade, the number of drugs formulated in the patches has hardly increased, and there has been little change in the composition of the patch systems. Modifications have been mostly limited to refinements of the materials used. The present review article explores the overall study on transdermal drug delivery system (TDDS which leads to novel drug delivery system (NDDS.

  12. Radionuclide interaction with clays in dilute and heavily compacted systems: a critical review.

    Science.gov (United States)

    Miller, Andrew W; Wang, Yifeng

    2012-02-21

    Given the unique properties of clays (i.e., low permeability and high ion sorption/exchange capacity), clays or clay formations have been proposed either as an engineered material or as a geologic medium for nuclear waste isolation and disposal. A credible evaluation of such disposal systems relies on the ability to predict the behavior of these materials under a wide range of thermal-hydrological-mechanical-chemical (THMc) conditions. Current model couplings between THM and chemical processes are simplistic and limited in scope. This review focuses on the uptake of radionuclides onto clay materials as controlled by mineral composition, structure, and texture (e.g., pore size distribution), and emphasizes the connections between sorption chemistry and mechanical compaction. Variable uptake behavior of an array of elements has been observed on various clays as a function of increasing compaction due to changes in pore size and structure, hydration energy, and overlapping electric double layers. The causes for this variability are divided between "internal" (based on the fundamental structure and composition of the clay minerals) and "external" (caused by a force external to the clay). New techniques need to be developed to exploit known variations in clay mineralogy to separate internal from external effects.

  13. Detecting and Attributing External Influences on the Climate System: A Review of Recent Advances

    Energy Technology Data Exchange (ETDEWEB)

    Barnett, T; Zwiers, F; Hegerl, G; Allen, M; Crowley, T; Gillett, N; Hasselmann, K; Jones, P; Santer, B; Schnur, R; Stott, P; Taylor, K; Tett, S

    2005-01-26

    We review recent research that assesses evidence for the detection of anthropogenic and natural external influences on the climate. Externally driven climate change has been detected by a number of investigators in independent data covering many parts of the climate system, including surface temperature on global and large regional scales, ocean-heat content, atmospheric circulation, and variables of the free atmosphere, such as atmospheric temperature and tropopause height. The influence of external forcing is also clearly discernible in reconstructions of hemispheric scale temperature of the last millennium. These observed climate changes are very unlikely to be due only to natural internal climate variability, and they are consistent with the responses to anthropogenic and natural external forcing of the climate system that are simulated with climate models. The evidence indicates that natural drivers such as solar variability and volcanic activity are at most partially responsible for the large-scale temperature changes observed over the past century, and that a large fraction of the warming over the last 50 years can be attributed to greenhouse gas increases. Thus the recent research supports and strengthens the IPCC Third Assessment Report conclusion that ''most of the global warming over the past 50 years is likely due to the anthropogenic increase in greenhouse gases''.

  14. Enzyme Stability and Activity in Non-Aqueous Reaction Systems: A Mini Review

    Directory of Open Access Journals (Sweden)

    Shihui Wang

    2016-02-01

    Full Text Available Enormous interest in biocatalysis in non-aqueous phase has recently been triggered due to the merits of good enantioselectivity, reverse thermodynamic equilibrium, and no water-dependent side reactions. It has been demonstrated that enzyme has high activity and stability in non-aqueous media, and the variation of enzyme activity is attributed to its conformational modifications. This review comprehensively addresses the stability and activity of the intact enzymes in various non-aqueous systems, such as organic solvents, ionic liquids, sub-/super-critical fluids and their combined mixtures. It has been revealed that critical factors such as Log P, functional groups and the molecular structures of the solvents define the microenvironment surrounding the enzyme molecule and affect enzyme tertiary and secondary structure, influencing enzyme catalytic properties. Therefore, it is of high importance for biocatalysis in non-aqueous media to elucidate the links between the microenvironment surrounding enzyme surface and its stability and activity. In fact, a better understanding of the correlation between different non-aqueous environments and enzyme structure, stability and activity can contribute to identifying the most suitable reaction medium for a given biotransformation.

  15. Bonding between oxide ceramics and adhesive cement systems: a systematic review.

    Science.gov (United States)

    Papia, Evaggelia; Larsson, Christel; du Toit, Madeleine; Vult von Steyern, Per

    2014-02-01

    The following aims were set for this systematic literature review: (a) to make an inventory of existing methods to achieve bondable surfaces on oxide ceramics and (b) to evaluate which methods might provide sufficient bond strength. Current literature of in vitro studies regarding bond strength achieved using different surface treatments on oxide ceramics in combination with adhesive cement systems was selected from PubMed and systematically analyzed and completed with reference tracking. The total number of publications included for aim a was 127 studies, 23 of which were used for aim b. The surface treatments are divided into seven main groups: as-produced, grinding/polishing, airborne particle abrasion, surface coating, laser treatment, acid treatment, and primer treatment. There are large variations, making comparison of the studies difficult. An as-produced surface of oxide ceramic needs to be surface treated to achieve durable bond strength. Abrasive surface treatment and/or silica-coating treatment with the use of primer treatment can provide sufficient bond strength for bonding oxide ceramics. This conclusion, however, needs to be confirmed by clinical studies. There is no universal surface treatment. Consideration should be given to the specific materials to be cemented and to the adhesive cement system to be used.

  16. The Performance and Fouling Control of Submerged Hollow Fiber (HF Systems: A Review

    Directory of Open Access Journals (Sweden)

    Ebrahim Akhondi

    2017-07-01

    Full Text Available The submerged membrane filtration concept is well-established for low-pressure microfiltration (MF and ultrafiltration (UF applications in the water industry, and has become a mainstream technology for surface-water treatment, pretreatment prior to reverse osmosis (RO, and membrane bioreactors (MBRs. Compared to submerged flat sheet (FS membranes, submerged hollow fiber (HF membranes are more common due to their advantages of higher packing density, the ability to induce movement by mechanisms such as bubbling, and the feasibility of backwashing. In view of the importance of submerged HF processes, this review aims to provide a comprehensive landscape of the current state-of-the-art systems, to serve as a guide for further improvements in submerged HF membranes and their applications. The topics covered include recent developments in submerged hollow fiber membrane systems, the challenges and developments in fouling-control methods, and treatment protocols for membrane permeability recovery. The highlighted research opportunities include optimizing the various means to manipulate the hydrodynamics for fouling mitigation, developing online monitoring devices, and extending the submerged HF concept beyond filtration.

  17. Aeolian sediment transport and landforms in managed coastal systems: A review

    Science.gov (United States)

    Jackson, Nancy L.; Nordstrom, Karl F.

    2011-11-01

    Humans modify beaches and dunes and aeolian transport potential by building structures, walking or driving, extracting resources, accommodating recreation, increasing levels of protection, removing storm deposits, or restoring landforms and habitats. The effects of human adjustments are reviewed here in terms of cross-shore zones because humans tend to compartmentalize landforms and habitats through their actions and regulations. Common human modifications in the beach zone include nourishing beaches, constructing shore protection structures and raking to remove litter. Modifications affecting the dune zone include altering the location, size and stability of dunes using sand-trapping fences, vegetation plantings and bulldozers or replacing dunes with shore-parallel structures. Modifications affecting the landward zone include buildings, roads, and parking lots. Landform and habitat resilience requires levels of dynamism and geomorphic complexity not often found in managed systems. Preserving or enhancing dynamism and complexity requires emphasis on innovative designs rooted in geomorphological and aeolian research. Future studies are suggested for: (1) quantifying the effect of small and large scale beach nourishment designs and sediment characteristics on dune initiation, development, and evolution; (2) quantifying the extent to which size and spacing of human structures and landform alterations inhibit sediment transfers alongshore or onshore; (3) identifying the advantages or disadvantages of "niche" dunes formed by structures; (4) providing quantitative data on the effects of raking or driving on the beach; (5) identifying the role of aeolian landforms on private properties; and (6) identifying alternative ways of employing sand fences and vegetation plantings to increase topographic and habitat diversity.

  18. Health Benefits of Anthocyanins and Their Encapsulation for Potential Use in Food Systems: A Review.

    Science.gov (United States)

    Yousuf, Basharat; Gul, Khalid; Wani, Ali Abas; Singh, Preeti

    2016-10-01

    Anthocyanins are one of the six subgroups of large and widespread group of plant constituents known as flavonoids. These are responsible for the bright and attractive orange, red, purple, and blue colors of most fruits, vegetables, flowers and some cereal grains. More than 600 structurally distinct anthocyanins have been identified in nature. Earlier, anthocyanins were only known for their coloring properties but now interest in anthocyanin pigments has intensified because of their possible health benefits as dietary antioxidants, which help to prevent neuronal diseases, cardiovascular illnesses, cancer, diabetes, inflammation, and many such others diseases. Ability of anthocyanins to counter oxidants makes them atherosclerosis fighters. Therefore, anthocyanin-rich foods may help to boost overall health by offering an array of nutrients. However, the incorporation of anthocyanins into food and medical products is a challenging task due to their low stability toward environmental conditions during processing and storage. Encapsulation seems to be an efficient way to introduce such compounds into these products. Encapsulating agents act as a protector coat against ambient adverse conditions such as light, humidity, and oxygen. Encapsulated bioactive compounds are easier to handle and offer improved stability. The main objective of this review is to explore health benefits of anthocyanins and their extraction, characterization, encapsulation, and delivery.

  19. The Mediterranean Sea system: a review and an introduction to the special issue

    Directory of Open Access Journals (Sweden)

    T. Tanhua

    2013-09-01

    Full Text Available The Mediterranean Sea is a semi-enclosed sea characterized by high salinities, temperatures and densities. The net evaporation exceeds the precipitation, driving an anti-estuarine circulation through the Strait of Gibraltar, contributing to very low nutrient concentrations. The Mediterranean Sea has an active overturning circulation, one shallow cell that communicates directly with the Atlantic Ocean, and two deep overturning cells, one in each of the two main basins. It is surrounded by populated areas and is thus sensitive to anthropogenic forcing. Several dramatic changes in the oceanographic and biogeochemical conditions have been observed during the past several decades, emphasizing the need to better monitor and understand the changing conditions and their drivers. During 2011 three oceanographic cruises were conducted in a coordinated fashion in order to produce baseline data of important physical and biogeochemical parameters that can be compared to historic data and be used as reference for future observational campaigns. In this article we provide information on the Mediterranean Sea oceanographic situation, and present a short review that will serve as background information for the special issue in Ocean Science on "Physical, chemical and biological oceanography of the Mediterranean Sea". An important contribution of this article is the set of figures showing the large-scale distributions of physical and chemical properties along the full length of the Mediterranean Sea.

  20. Predicting the mode of flow in pneumatic conveying systems-A review

    Institute of Scientific and Technical Information of China (English)

    Mark G.Jones; Kenneth C.Williams

    2008-01-01

    An initial prediction of the particulate mode of flow in pneumatic conveying systems is beneficial as this knowledge can provide clearer direction to the pneumatic conveying design process.There are three general categories of modes of flow,two dense flows:fluidised dense phase and plug flow,and dilute phase only.Detailed in this paper is a review of the commonly used and available techniques for predicting mode of flow.Two types of predictive charts were defined:basic particle parameter based (e.g.particle size and density) and air-particle parameter based (e.g.permeability and de-aeration).The basic particle techniques were found to have strong and weak areas of predictive ability,on the basis of a comparison with data from materials with known mode of flow capability.It was found that there was only slight improvement in predictive ability when the particle density was replaced by loose-poured bulk density in the basic parameter techniques.The air-particle-parameter-based techniques also showed well-defined regions for mode of flow prediction though the data set used was smaller than that for the basic techniques.Also,it was found to be difficult to utilise de-aeration values from different researchers and subsequently,an air-particle-based technique was developed which does not require any de-aeration parameter in its assessment.

  1. ORAL COLON TARGETED DRUG DELIVERY SYSTEM: A REVIEW ON CURRENT AND NOVEL PERSPECTIVES

    Directory of Open Access Journals (Sweden)

    Asija Rajesh

    2012-10-01

    Full Text Available Small intestine is mostly the site for drug absorption but in some cases the drug needs to be targeted to colon due to some factors like local colonic disease, degradation related conditions, delayed release of drugs, systemic delivery of protein and peptide drugs etc. Colon targeted drug delivery is important and relatively new concept for the absorption of drugs because it offers almost neutral pH and long residence time, thereby increasing the drug absorption. Colon has proved to be a site for the absorption of poorly soluble drugs. For the successful targeting of drugs to colon the dosage form should be designed such that it prevents the drug release in upper GIT and releasing it in the colonic region. This review article discusses in brief about introduction of colon along with the novel and emerging technologies for colon targeting of drug molecule. Treatment of these diseases with colon-specific drug delivery system provides an interesting alternative over systemic drug administration because of lower dosing and fewer systemic side effects.

  2. Phytol a Natural Diterpenoid with Pharmacological Applications on Central Nervous System: A Review.

    Science.gov (United States)

    Pereira Costa, Jessica; da Silva Oliveira, Johanssy; Mario Rezende Junior, Luis; de Freitas, Rivelilson Mendes

    2014-01-01

    Phytol (3,7,11,15-tetramethylhexadec-2-en-1-ol), a diterpene member of long and ramified chain of unsaturated acyclic alcohols. The objective of study was to conduct a systematic review of this diterpene and its pharmaceutical applications in Nervous System diseases in humans and/or rodents. Periodicals bases, such as ScienceDirect and PubMed, were used, as well as technological basis of European Patent Office, World Intellectual Property Organization, United States Patent and Trademark Office, Derwent Innovations Index(®), Latin American Bank of Patents and data base of Instituto Nacional de Propriedade Industrial (INPI-National Institute of Industrial Property). The software EndNote-X5 was utilized as reference with the keywords: phytol, anxiolytic, antidepressant and anticonvulsant and their correlations in English, Spanish and Portuguese from January 2003 to June 2014. There are many publications on phytol in international literature. However, there is a reduced number of articles related to pharmacological activities proposed here. In reference to technological bases, patents present a wide range of pharmacological and commercial applications as cosmetics, hypolipodemic, anxiolytic and antidepressant. Therefore, it is necessary to explore phytol molecules, which present high pharmacological potential from scientific and technological points of view, in search of transference of technologies to generate economical and industrial growth.

  3. The effects of phthalates in the cardiovascular and reproductive systems: A review.

    Science.gov (United States)

    Mariana, Melissa; Feiteiro, Joana; Verde, Ignacio; Cairrao, Elisa

    2016-09-01

    Every year millions of tons of plastic are produced around the world and humans are increasingly exposed to them. This constant exposure to plastics has raised some concerns against human health, particularly when it comes to phthalates. These compounds have endocrine-disrupting properties, as they have the ability to bind molecular targets in the body and interfere with hormonal function and quantity. The main use of phthalates is to give flexibility to polyvinyl chloride (PVC) polymers. Phthalates are found in a variety of industrial and consumer products, and as they are not covalently bound to the plastic, phthalates contaminate the environment from which human exposure occurs. Studies in human and animal populations suggest a correlation between phthalate exposure and adverse health outcomes, particularly at the reproductive and cardiovascular systems, however there is much less information about the phthalate toxicity of the later. Thus, the main purpose of this review is to present the studies relating the effects already stated of phthalates on the cardiovascular and reproductive systems, and also present the link between these two systems.

  4. Web GIS-Based Public Health Surveillance Systems: A Systematic Review

    Directory of Open Access Journals (Sweden)

    Hui Luan

    2014-04-01

    Full Text Available Web Geographic Information System (Web GIS has been extensively and successfully exploited in various arenas. However, to date, the application of this technology in public health surveillance has yet to be systematically explored in the Web 2.0 era. We reviewed existing Web GIS-based Public Health Surveillance Systems (WGPHSSs and assessed them based on 20 indicators adapted from previous studies. The indicators comprehensively cover various aspects of WGPHSS development, including metadata, data, cartography, data analysis, and technical aspects. Our literature search identified 58 relevant journal articles and 27 eligible WGPHSSs. Analyses of results revealed that WGPHSSs were frequently used for infectious-disease surveillance, and that geographical and performance inequalities existed in their development. The latest Web and Web GIS technologies have been used in developing WGPHSSs; however, significant deficiencies in data analysis, system compatibility, maintenance, and accessibility exist. A balance between public health surveillance and privacy concerns has yet to be struck. Use of news and social media as well as Web-user searching records as data sources, participatory public health surveillance, collaborations among health sectors at different spatial levels and among various disciplines, adaption or reuse of existing WGPHSSs, and adoption of geomashup and open-source development models were identified as the directions for advancing WGPHSSs.

  5. Contribution of Wastewater Treatment Plant Effluents to Nutrient Dynamics in Aquatic Systems: A Review

    Science.gov (United States)

    Carey, Richard O.; Migliaccio, Kati W.

    2009-08-01

    Excessive nutrient loading (considering nitrogen and phosphorus) is a major ongoing threat to water quality and here we review the impact of nutrient discharges from wastewater treatment plants (WWTPs) to United States (U.S.) freshwater systems. While urban and agricultural land uses are significant nonpoint nutrient contributors, effluent from point sources such as WWTPs can overwhelm receiving waters, effectively dominating hydrological characteristics and regulating instream nutrient processes. Population growth, increased wastewater volumes, and sustainability of critical water resources have all been key factors influencing the extent of wastewater treatment. Reducing nutrient concentrations in wastewater is an important aspect of water quality management because excessive nutrient concentrations often prevent water bodies from meeting designated uses. WWTPs employ numerous physical, chemical, and biological methods to improve effluent water quality but nutrient removal requires advanced treatment and infrastructure that may be economically prohibitive. Therefore, effluent nutrient concentrations vary depending on the particular processes used to treat influent wastewater. Increasingly stringent regulations regarding nutrient concentrations in discharged effluent, along with greater freshwater demand in populous areas, have led to the development of extensive water recycling programs within many U.S. regions. Reuse programs provide an opportunity to reduce or eliminate direct nutrient discharges to receiving waters while allowing for the beneficial use of reclaimed water. However, nutrients in reclaimed water can still be a concern for reuse applications, such as agricultural and landscape irrigation.

  6. Effect of Exposure to Non-ionizing Radiation (Electromagnetic Fields on Human System: A Literature Review

    Directory of Open Access Journals (Sweden)

    Paula Rubya Souza C and acirc;mara

    2014-08-01

    Full Text Available The indiscriminate presence of radio base stations, which emit non-ionizing radiation (NIR, as well as the frequent use of mobile phones, can cause increased susceptibility of populations to the emergence of diseases such as cancers of the head and neck, biochemical, hematopoietic and hepatic changes, among others. Exposure to physical contamination, including NIR, has been implicated in numerous diseases, raising concerns about the widespread sources of exposure to this type of radiation. This paper reviews studies that have assessed associations between likely exposure to electromagnetic fields, such as radiofrequency transmissions, and many kinds of human diseases including cancer, as well as alerts to the current knowledge on the association between environmental exposure to NIR and the risk of development of adverse human health effects. This way, there appears to be an urgent need to reconsider exposure limits for low frequency and static magnetic fields, based on combined experimental and epidemiological research. [J Interdiscipl Histopathol 2014; 2(4.000: 187-190

  7. Groundwater and security

    NARCIS (Netherlands)

    Conti, K.I.; Kukurić, N.; Gupta, J.; Pahl-Wostl, C.; Bhaduri, A.; Gupta, J.

    2016-01-01

    Humans abstract two hundred times more groundwater than oil, annually. Ironically, the role of groundwater in water management and supply is underappreciated, partially due to its invisibility. By conducting a literature survey and investigating groundwater information databases, this chapter answer

  8. Role of Endogenous and Exogenous Tocopherols in the Lipid Stability of Marine Oil Systems: A Review

    Directory of Open Access Journals (Sweden)

    Guadalupe Miroslava Suárez-Jiménez

    2016-11-01

    Full Text Available In marine organisms primarily intended for human consumption, the quality of the muscle and the extracted oils may be affected by lipid oxidation during storage, even at low temperatures. This has led to a search for alternatives to maintain quality. In this sense, antioxidant compounds have been used to prevent such lipid deterioration. Among the most used compounds are tocopherols, which, due to their natural origin, have become an excellent alternative to prevent or retard lipid oxidation and maintain the quality of marine products. Tocopherols as antioxidants have been studied both exogenously and endogenously. Exogenous tocopherols are often used by incorporating them into plastic packaging films or adding them directly to fish oil. It has been observed that exogenous tocopherols incorporated in low concentrations maintain the quality of both muscle and the extracted oils during food storage. However, it has been reported that tocopherols applied at higher concentrations act as a prooxidant molecule, probably because their reactions with singlet oxygen may generate free radicals and cause the oxidation of polyunsaturated fatty acids in fish oils. However, when tocopherols are included in a fish diet (endogenous tocopherols, the antioxidant effect on the muscle lipids is more effective due to their incorporation into the membrane lipids, which can help extend the shelf life of seafood by reducing the lipid deterioration that occurs due to antioxidant synergy with other phenolic compounds used supplements in fish muscle. This review focuses on the most important studies in this field and highlights the potential of using tocopherols as antioxidants in marine oils.

  9. Research developments in methods to reduce the carbon footprint of the food system: a review.

    Science.gov (United States)

    Xu, Zhongyue; Sun, Da-Wen; Zeng, Xin-An; Liu, Dan; Pu, Hongbin

    2015-01-01

    Global warming is a worldwide issue with its evident impact across a wide range of systems and sectors. It is caused by a number of greenhouse gases (GHGs) emissions, in which food system has made up of a large part. Recently, reduction of GHG emissions has become an urgent issue to be resolved in the food system. Many governments and organizations are making great endeavors to alleviate the adverse effect of this phenomenon. In this review, methods to reduce the carbon footprint within the life cycle of a food system are presented from the technical, consumption behavior and environmental policies perspectives. The whole food system including raw material acquisition, processing, packaging, preservation, transportation, consumption, and disposal are covered. Improving management techniques, and adopting advanced technology and equipment are critical for every stage of a food system. Rational site selection is important to alleviate the influence of land use change. In addition, environmental choices of packaging stage, reduction in refrigeration dependence, and correct waste treatment are essential to reduce the total carbon footprint of the production. However, only technical methods cannot radically reverse the trend of climate change, as consumption behaviors present a great deal of influence over climate change. Appropriate purchase patterns and substitution within food product categories by low carbon products can reduce GHG emissions. Development of methods to calculate the carbon footprint of every kind of food and its processing technology enable people to make environmental choice. Policy can shape and cultivate the new code of consumption and influence the direction of emerging technology and science. From political perspectives, government intervention and carbon offset are common tools, especially for carbon tax and a real or implicit price of carbon. Finally, by mitigating the methodologies described above, the rate and magnitude of climate changes

  10. Barriers in the Implementation of Health Information Systems: A Scoping Review

    Directory of Open Access Journals (Sweden)

    Florin STAMATIAN

    2013-12-01

    Full Text Available Context. A well-developed health information system which is implemented according to present standards allows a healthcare quality increase. Our study aims at providing an overview of the barriers which were encountered in the process of implementing the health information systems by reviewing the literature connected to Europe and the United States of America. Methodology. We searched within five databases (Cochrane Library, Google Scholar, PubMed, ScienceDirect and Scopus for the exact phrase ‘implementation health information system’ along with the name of each European country/USA state. Relevance was then tested by scanning titles and abstracts. The third and final step involved assessing all the articles in order to set their relevance and a data extraction tool was created, containing the name of the state/country that the article reports data on, the article citation and the challenges identified. Results. The barriers identified were classified in four major categories: technical, organizational, behavioral/human and financial. Seemingly, Europe (41 articles and USA (20 articles are facing the same issues in the implementation of a health information system. No major difference between EU and non-EU countries was found after our analysis with regards to the identified barriers. Discussion. Even if recommendations and solutions are continuously being developed in order to solve these barriers, the implementation of a new health information system must be very detailed in order to face all these problems. Additionally, further research is required in order to evaluate their impact on the successful implementation of a health information system.

  11. Assessing the sustainability of freshwater systems: A critical review of composite indicators.

    Science.gov (United States)

    Vollmer, Derek; Regan, Helen M; Andelman, Sandy J

    2016-11-01

    Quantitative indicators are a common means of assessing the complex dimensions of a sustainable freshwater system, and framing scientific knowledge for policy and decision makers. There is an abundance of indicators in use, but considerable variation in terms of what is being measured and how indicators are applied, making it difficult for end-users to identify suitable assessment methods. We review 95 water-related indices and analyze them along their normative, procedural, and systemic dimensions to better understand how problems are being defined, highlight overlaps and differences, and identify the context(s) in which a particular index is useful. We also analyze the intended use, end-users, and geographic scale of application for each index. We find that risk assessment is the most common application (n = 25), with indices in this group typically focusing either on hazard identification (biophysical assessments) or vulnerability of human populations. Indices that measure freshwater ecological health are not explicitly linking these indicators to ecosystem services, and in fact the concept of ecosystem services is rarely (n = 3) used for indicator selection. Resource managers are the most common group of intended end-users (n = 25), but while 28 indices involved consultation with potential end-users, 11 did not specify an intended use. We conclude that indices can be applied as solution-oriented tools, evaluating scenarios and identifying tradeoffs among services and beneficiaries, rather than only assessing and monitoring existing conditions. Finally, earlier engagement of end-users is recommended to help researchers find the right balance among indices' salience, legitimacy, and credibility and thus improve their decision relevance.

  12. Sheepmeat flavor and the effect of different feeding systems: a review.

    Science.gov (United States)

    Watkins, Peter J; Frank, Damian; Singh, Tanoj K; Young, Owen A; Warner, Robyn D

    2013-04-17

    Lamb has a unique flavor, distinct from other popular red meats. Although flavor underpins lamb's popularity, it can also be an impediment to consumer acceptance. Lack of familiarity with sheepmeat flavor itself can be a barrier for some consumers, and undesirable feed-induced flavors may also compromise acceptability. Against the backdrop of climate uncertainty and unpredictable rainfall patterns, sheep producers are turning to alternatives to traditional grazing pasture systems. Historically, pasture has been the predominant feed system for lamb production in Australia and around the world. It is for this reason that there has been a focus on "pastoral" flavor in sheep meat. Pasture-associated flavors may be accepted as "normal" by consumers accustomed to meat from pasture-fed sheep; however, these flavors may be unfamiliar to consumers of meat produced from grain-fed and other feed systems. Over the past few decades, studies examining the impacts of different feeds on lamb meat quality have yielded variable consumer responses ranging from "no effect" to "unacceptable", illustrating the diverse and sometimes inconsistent impacts of different forages on sheepmeat flavor. Despite considerable research, there is no consensus on which volatiles are essential for desirable lamb aroma and how they differ compared to other red meats, for example, beef. In contrast, comparatively little work has focused specifically on the nonvolatile taste components of lamb flavor. Diet also affects the amount of intramuscular fat and its fatty acid composition in the meat, which has a direct effect on meat juiciness and texture as well as flavor, and its release during eating. The effect of diet is far from simple and much still needs to be learned. An integrated approach that encompasses all input variables is required to better understand the impact of the feed and related systems on sheepmeat flavor. This review brings together recent research findings and proposes some novel

  13. Structure of volcano plumbing systems: A review of multi-parametric effects

    Science.gov (United States)

    Tibaldi, Alessandro

    2015-06-01

    Magma is transported and stored in the crust mostly through networks of planar structures (intrusive sheets), ranging from vertical dykes to inclined sheets and horizontal sills, and magma chambers, which make up the plumbing system of volcanoes. This study presents an overview of plumbing systems imaged at different depths and geodynamic settings, in order to contribute to assessing the factors that control their geometry. Data were derived from personal field surveys and through the analysis of publications; observations include local lithology and tectonics of the host rock with special reference to local fault kinematics and related stress tensor, regional tectonics (general kinematics and far-field stress tensors), geology and shape of the volcano, topographic settings, and structural and petrochemical characteristics of the plumbing system. Information from active volcanoes and eroded extinct volcanoes is discussed; the shallow plumbing system of active volcanoes has been reconstructed by combining available geophysical data with field information derived from outcropping sheets, morphometric analyses of pyroclastic cones, and the orientation and location of eruptive fissures. The study of eroded volcanoes enabled to assess the plumbing system geometry at deeper levels in the core of the edifice or underneath the volcano-substratum interface. Key sites are presented in extensional, transcurrent and contractional tectonic settings from North and South-America, Iceland, the Southern Tyrrhenian Sea and Africa. The types of sheet arrangements illustrated include swarms of parallel dykes, diverging rift patterns, centrally-inclined sheets, ring and radial dykes, circum-lateral collapse sheets, sills, and mixed members. This review shows that intrusive sheet emplacement at a volcano depends upon the combination of several local and regional factors, some of which are difficult to be constrained. While much progress has been made, it is still very challenging to

  14. Optimal and Sustainable Groundwater Extraction

    Directory of Open Access Journals (Sweden)

    Christopher A. Wada

    2010-08-01

    Full Text Available With climate change exacerbating over-exploitation, groundwater scarcity looms as an increasingly critical issue worldwide. Minimizing the adverse effects of scarcity requires optimal as well as sustainable patterns of groundwater management. We review the many sustainable paths for groundwater extraction from a coastal aquifer and show how to find the particular sustainable path that is welfare maximizing. In some cases the optimal path converges to the maximum sustainable yield. For sufficiently convex extraction costs, the extraction path converges to an internal steady state above the level of maximum sustainable yield. We describe the challenges facing groundwater managers faced with multiple aquifers, the prospect of using recycled water, and the interdependence with watershed management. The integrated water management thus described results in less water scarcity and higher total welfare gains from groundwater use. The framework also can be applied to climate-change specifications about the frequency, duration, and intensity of precipitation by comparing before and after optimal management. For the case of South Oahu in Hawaii, the prospect of climate change increases the gains of integrated groundwater management.

  15. Exploring the significance of structural hierarchy in material systems-A review

    Science.gov (United States)

    Pan, Ning

    2014-06-01

    to make an effort to explore, identify, derive, or theorize some generic principles based on the existing results, not to offer another comprehensive review of current research activities in the fields for that there already exist some excellent ones. This paper examines the related topics with several approaches to not only reveal the underlying geometrical and physical mechanisms but also to emphasize the ways in which such mechanisms may be applied to developing engineered material systems with novel properties.

  16. Organic amendments as restoration techniques in degraded arid and semiarid systems: A review

    Science.gov (United States)

    Hueso-González, Paloma; Muñoz-Rojas, Miriam

    2017-04-01

    There is an increasing concern at the global scale about interrelated environmental problems such as soil degradation, desertification, erosion, and climate change impacts (Hueso-Gonzalez et al., 2014). Indiscriminate use of agro-chemicals, excessive and deep tillage, excessive irrigation, among many others factors, have largely contributed to soil degradation, particularly in arid and semi-arid areas (Lal, 2008). Soil is an essential non-renewable resource with extremely slow formation and regeneration potential (Muñoz-Rojas et al., 2016a and c, Martínez-Murillo et al., 2016). The decline in organic matter content of many soils is becoming a major cause of soil degradation, particularly in dryland regions (Muñoz-Rojas et al., 2016b) where low soil fertility cannot maintain sustainable production in many cases (Hueso-González et al., 2015). The use of soil organic amendments is a common practice in agricultural management and land restoration that can help to improve physical and chemical soil properties, soil structure, temperature and humidity conditions, as well as nutrient contents which are essential for plant growth (Guerrero et al., 2001). Under degraded conditions, several studies have shown their benefits for improving soil physical, chemical and biological properties (Jordan et al., 2010 and 2011). However, there are many research gaps in the knowledge of the effects of climatic conditions on their application, as well as the adequate types of amendment and doses and decomposition rates, (Hueso-Gonzalez,2016). All these factors are crucial for the success in their application. Here, we review long-term experiments worldwide studying the benefits associated with the application of organic materials, particularly, in restoration of arid and semiarid ecosystems together with the possible threats and risks that can result from their use. We will specifically adress: (1) type of amended and benefits arising from their use, (2) application methods and more

  17. Managing Watersheds as Couple Human-Natural Systems: A Review of Research Opportunities

    Science.gov (United States)

    Cai, X.

    2011-12-01

    evidenced by 1) institutional innovation for integrated watershed management; 2) real-world management practices involving multidisciplinary expertise; 3) growing role of economics in systems analysis; 4) enhanced research programs such as the CHNS program and Water, Sustainability and Climate (WSC) program at the US National Science Foundation (NSF). Furthermore, recent scientific and technological developments are expected to accommodate integrated watershed system analysis approaches, such as: 1) increasing availability of distributed digital datasets especially from remote sensing products (e.g. digital watersheds); 2) distributed and semi-distributed watershed hydrologic modeling; 3) enhanced hydroclimatic monitoring and forecast; 4) identified evidences of vulnerability and threshold behavior of watersheds; and 5) continuing improvements in computational and optimization algorithms. Managing watersheds as CHNS will be critical for watershed sustainability, which ensures that human societies will benefit forever from the watershed through development of harmonious relationships between human and natural systems. This presentation will provide a review of the research opportunities that take advantage of the concept of CHNS and associated scientific, technological and institutional innovations/developments.

  18. Review of submarine groundwater discharge (SGD) in coastal zones of the Southeast and Gulf Coast regions of the United States with management implications.

    Science.gov (United States)

    McCoy, C A; Corbett, D R

    2009-01-01

    Groundwater serves as the primary drinking water source for over half of the coastal populations of the Southeast and Gulf Coast regions, two of the fastest growing regions in the United States. Increased demand for this resource has exceeded sustainable yields in many areas and induced saltwater intrusion of coastal aquifers. A process associated with coastal groundwater, submarine groundwater discharge (SGD), has been documented as a source of subsurface fluids to coastal ocean environments throughout the Southeast and Gulf Coast regions and is potentially a significant contributor to nearshore water and geochemical budgets (i.e., nutrients, carbon, trace metals) in many coastal regions. The importance of groundwater as a drinking water source for coastal populations and the influences of submarine groundwater discharge to the coastal ocean warrant increased research and management of this resource. This paper highlights findings from recent SGD studies on three hydrogeologically different continental margins (Onslow Bay, NC, southern Florida, and the Louisiana margin), provides background on the common methods of assessing SGD, and suggests a regional management plan for coastal groundwater resources. Suggested strategies call for assessments of SGD in areas of potentially significant discharge, development of new monitoring networks, and the incorporation of a regional coastal groundwater resources council.

  19. Aespoe Task Force on modelling of groundwater flow and transport of solutes. Review of Tasks 6D, 6E, 6F and 6F2

    Energy Technology Data Exchange (ETDEWEB)

    Hodgkinson, David (Quintessa, Henley-on-Thames (GB))

    2007-09-15

    This report forms part of an independent review of the specifications, execution and results of Task 6 of the Aespoe Task Force on Modelling of Groundwater Flow and Transport of Solutes, which is seeking to provide a bridge between site characterization and performance assessment approaches to modelling solute transport in fractured rock. The objectives of Task 6 are: To assess simplifications used in Performance Assessment (PA) models. To determine how, and to what extent, experimental tracer and flow experiments can constrain the range of parameters used in PA models. To support the design of Site Characterisation (SC) programmes to ensure that the results have optimal value for performance assessment calculations. To improve the understanding of site-specific flow and transport behaviour at different scales using site characterisation models. The present report is concerned with Tasks 6D, 6E, 6F and 6F2. It follows on from two previous reviews of Tasks 6A, 6B and 6B2, and Task 6C. In Task 6D the transport of tracers through a fracture network is modelled using the conditions of the C2 TRUE-Block Scale tracer test, based on the synthetic structural model developed in Task 6C. Task 6E extends the Task 6D transport calculations to a reference set of PA time scales and boundary conditions. Task 6F consists of a series of 'benchmark' studies on single features from the Task 6C hydrostructural model in order to improve the understanding of differences between the participating models. Task 6F2 utilises models set up for Tasks 6E and 6F to perform additional sensitivity studies with the aim of increasing the understanding of how models behave, the reason for differences in modelling results, and the sensitivity of models to various assumptions and parameter values. Eight modelling teams representing five organisations participated in this exercise using Discrete Fracture Network (DFN), continuum and channel network concepts implemented in a range of different

  20. The hydrogeologic framework and a reconnaissance of ground-water quality in the Piedmont Province of North Carolina, with a design for future study

    Science.gov (United States)

    Harned, Douglas

    1989-01-01

    The U.S. Geological Survey is investigating the relation of ground- water quality and land use in the regolith and fractured rock ground-water system of the North Carolina Piedmont. The initial phase of this study provides a description of the ground-water flow system and a review of available ground-water data and formulates hypotheses that guide the design of a water-quality monitoring network for study of selected areas. In the Piedmont, the solid igneous and metamorphic bedrock grades upward into unweathered fractured rock that is covered by a transition zone of highly-fractured, partially weathered rock, clay-rich saprolite, and the soil. The fractured bedrock, transition zone, saprolite, and soil make up a complex flow system. A review of available ground-water quality data shows a lack of information about organic compounds and trace metals and changes in ground- water quality with depth. Land use, soils, and geology significantly influence ground-water quality. The hypotheses that need to be tested in the next study phase are: (1) that ground-water contamination can be related to land use, and (2) that the transition zone between bedrock and regolith serves as a primary transmitter of contaminants. Monitoring of basins containing industrial, urban, residential, and agricultural land uses in future studies will help define the relation of ground-water quality to land use. Water quality at different depths in the flow system and in streams during base flow needs to be identified.

  1. Groundwater recharge: Accurately representing evapotranspiration

    CSIR Research Space (South Africa)

    Bugan, Richard DH

    2011-09-01

    Full Text Available Groundwater recharge is the basis for accurate estimation of groundwater resources, for determining the modes of water allocation and groundwater resource susceptibility to climate change. Accurate estimations of groundwater recharge with models...

  2. Geochemical Investigations of Groundwater Stability

    Energy Technology Data Exchange (ETDEWEB)

    Bath, Adrian [Intellisci Ltd., Loughborough (United Kingdom)

    2006-05-15

    The report describes geochemical parameters and methods that provide information about the hydrodynamic stability of groundwaters in low permeability fractured rocks that are potential hosts for radioactive waste repositories. Hydrodynamic stability describes the propensity for changes in groundwater flows over long timescales, in terms of flow rates and flow directions. Hydrodynamic changes may also cause changes in water compositions, but the related issue of geochemical stability of a potential repository host rock system is outside the scope of this report. The main approaches to assessing groundwater stability are numerical modelling, measurement and interpretation of geochemical indicators in groundwater compositions, and analyses and interpretations of secondary minerals and fluid inclusions in these minerals. This report covers the latter two topics, with emphasis on geochemical indicators. The extent to which palaeohydrogeology and geochemical stability indicators have been used in past safety cases is reviewed. It has been very variable, both in terms of the scenarios considered, the stability indicators considered and the extent to which the information was explicitly or implicitly used in assessing FEPs and scenarios in the safety cases. Geochemical indicators of hydrodynamic stability provide various categories of information that are of hydrogeological relevance. Information about groundwater mixing, flows and water sources is potentially provided by the total salinity of groundwaters, their contents of specific non-reactive solutes (principally chloride) and possibly of other solutes, the stable isotopic ratio of water, and certain characteristics of secondary minerals and fluid inclusions. Information pertaining directly to groundwater ages and the timing of water and solute movements is provided by isotopic systems including tritium, carbon-14, chlorine-36, stable oxygen and hydrogen isotopes, uranium isotopes and dissolved mobile gases in

  3. Review on research progress of Arc Hydro and Arc Hydro Groundwater hydrological data model%Arc Hydro与Arc Hydro Groundwater水文数据模型研究综述

    Institute of Scientific and Technical Information of China (English)

    崔素芳; 张保祥; 崔峻岭; 潘英华; 张振华; 吴泉源; 衣华鹏

    2016-01-01

    由于目前在地表水与地下水的联合模拟研究中备受青睐的Arc Hydro与Arc Hydro Groundwater水文数据模型能否应用于水文模拟尚缺少实证性研究,通过查阅大量文献资料,分析这两个水文数据模型的功能和优点,以及存在的问题和未来发展趋势。指出Arc Hydro模型虽然具备强大的水文分析与提取功能,但其本身并不能实现水文模拟,必须与独立的水文模型利用数据交换来完成水文模拟;Arc Hydro Groundwater模型虽然包含MODFLOW分析模型,但只能对MODFLOW模型输出的结果进行可视化处理,目前还不具备独立的地下水模拟功能。认为地表水与地下水联合模型与GIS耦合集成平台的开发将是未来研究的热点。%Arc Hydro and Arc Hydro Groundwater hydrological data model are favored by scholars in the joint simulation of surface water and groundwater, but empirical researches on whether hydrological simulation can apply Arc Hydro and Arc Hydro Groundwater model are lack. According to this problem, the functions and advantages of these two hydrological models were analyzed, furthermore, the remaining problems and the development trend were also discussed by a review of a large number of documents. It is pointed out that although Arc Hydro has function of strong hydrological analysis and extraction, this model cannot realize hydrological simulation, data exchange is necessary to complete hydrological simulation with independent hydrological model. Arc Hydro Groundwater contains MODFLOW analysis model, however, it only can visualize process for MODFLOW model outputs and does not yet have independent groundwater simulation function. The development of integrated platform combining joint simulation model of surface water and groundwater with GIS coupling is supposed to be a hot research.

  4. Groundwater Managment Districts

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset outlines the location of the five Groundwater Management Districts in Kansas. GMDs are locally formed and elected boards for regional groundwater...

  5. Groundwater Policy Research: Collaboration with Groundwater Conservation Districts in Texas

    OpenAIRE

    Johnson, Jeffrey W.; Johnson, Phillip N.; Guerrero, Bridget L.; Weinheimer, Justin; Amosson, Stephen H.; Almas, Lal K.; Golden, Bill B.; Wheeler-Cook, Erin

    2011-01-01

    The unique nature of the Ogallala Aquifer presents interesting and confounding problems for water policymakers who are coping with changing groundwater rules in Texas. The purpose of this article is to link previous efforts in water policy research for the Ogallala Aquifer in Texas with current collaborations that are ongoing with regional water planners. A chronological progression of economic water modeling efforts for the region is reviewed. The results of two recent collaborative studies ...

  6. Groundwater Policy Research: Collaboration with Groundwater Conservation Districts in Texas

    OpenAIRE

    Johnson, Jeffrey W.; Johnson, Phillip N.; Guerrero, Bridget L.; Weinheimer, Justin; Amosson, Stephen H.; Almas, Lal K.; Golden, Bill B.; Wheeler-Cook, Erin

    2011-01-01

    The unique nature of the Ogallala Aquifer presents interesting and confounding problems for water policymakers who are coping with changing groundwater rules in Texas. The purpose of this article is to link previous efforts in water policy research for the Ogallala Aquifer in Texas with current collaborations that are ongoing with regional water planners. A chronological progression of economic water modeling efforts for the region is reviewed. The results of two recent collaborative studies ...

  7. Modelling Urban diffuse pollution in groundwater

    Science.gov (United States)

    Jato, Musa; Smith, Martin; Cundy, Andrew

    2017-04-01

    Diffuse urban pollution of surface and ground waters is a growing concern in many cities and towns. Traffic-derived pollutants such as salts, heavy metals and polycyclic aromatic hydrocarbons (PAHs) may wash off road surfaces in soluble or particulate forms which later drain through soils and drainage systems into surface waters and groundwater. In Brighton, about 90% of drinking water supply comes from groundwater (derived from the Brighton Chalk block). In common with many groundwater sources the Chalk aquifer has been relatively extensively monitored and assessed for diffuse rural contaminants such as nitrate, but knowledge on the extent of contamination from road run-off is currently lacking. This project examines the transfer of traffic-derived contaminants from the road surface to the Chalk aquifer, via urban drainage systems. A transect of five boreholes have been sampled on a monthly basis and groundwater samples analysed to examine the concentrations of key, mainly road run-off derived, hydrocarbon and heavy metal contaminants in groundwater across the Brighton area. Trace concentrations of heavy metals and phenols have been observed in groundwater. Electrical conductivity changes in groundwater have also been used to assess local changes in ionic strength which may be associated with road-derived contaminants. This has been supplemented by systematic water and sediment sampling from urban gully pots, with further sampling planned from drainage and settlement ponds adjacent to major roads, to examine initial road to drainage system transport of major contaminants.

  8. Effects of microcystin-LR and cylindrospermopsin on plant-soil systems: A review of their relevance for agricultural plant quality and public health.

    Science.gov (United States)

    Machado, J; Campos, A; Vasconcelos, V; Freitas, M

    2017-02-01

    Toxic cyanobacterial blooms are recognized as an emerging environmental threat worldwide. Although microcystin-LR is the most frequently documented cyanotoxin, studies on cylindrospermopsin have been increasing due to the invasive nature of cylindrospermopsin-producing cyanobacteria. The number of studies regarding the effects of cyanotoxins on agricultural plants has increased in recent years, and it has been suggested that the presence of microcystin-LR and cylindrospermopsin in irrigation water may cause toxic effects in edible plants. The uptake of these cyanotoxins by agricultural plants has been shown to induce morphological and physiological changes that lead to a potential loss of productivity. There is also evidence that edible terrestrial plants can bioaccumulate cyanotoxins in their tissues in a concentration dependent-manner. Moreover, the number of consecutive cycles of watering and planting in addition to the potential persistence of microcystin-LR and cylindrospermopsin in the environment are likely to result in groundwater contamination. The use of cyanotoxin-contaminated water for agricultural purposes may therefore represent a threat to both food security and food safety. However, the deleterious effects of cyanotoxins on agricultural plants and public health seem to be dependent on the concentrations studied, which in most cases are non-environmentally relevant. Interestingly, at ecologically relevant concentrations, the productivity and nutritional quality of some agricultural plants seem not to be impaired and may even be enhanced. However, studies assessing if the potential tolerance of agricultural plants to these concentrations can result in cyanotoxin and allergen accumulation in the edible tissues are lacking. This review combines the most current information available regarding this topic with a realistic assessment of the impact of cyanobacterial toxins on agricultural plants, groundwater quality and public health.

  9. A review of seawater intrusion in the Nile Delta groundwater system – the basis for assessing impacts due to climate changes and water resources development

    NARCIS (Netherlands)

    Mabrouk, M.B.; Jonoski, A.; Solomatine, D.P.; Uhlenbrook, S.

    2013-01-01

    Serious environmental problems are emerging in the River Nile basin and its groundwater resources. Recent years have brought scientific evidence of climate change and development-induced environmental impacts globally as well as over Egypt. Some impacts are subtle, like decline of the Nile River wat

  10. DYNAMICS OF AGRICULTURAL GROUNDWATER EXTRACTION

    OpenAIRE

    Hellegers, Petra J.G.J.; Zilberman, David; van Ierland, Ekko C.

    2001-01-01

    Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is developed to study socially optimal agricultural shallow groundwater extraction patterns. It shows the importance of stock size to slow down changes in groundwater quality.

  11. DYNAMICS OF AGRICULTURAL GROUNDWATER EXTRACTION

    OpenAIRE

    Hellegers, Petra J.G.J.; Zilberman, David; van Ierland, Ekko C.

    2001-01-01

    Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is developed to study socially optimal agricultural shallow groundwater extraction patterns. It shows the importance of stock size to slow down changes in groundwater quality.

  12. Use of Additives in Bioremediation of Contaminated Groundwater and Soil

    Science.gov (United States)

    This chapter reviews application of additives used in bioremediation of chlorinated solvents and fuels for groundwater and soil remediation. Soluble carbon substrates are applicable to most site conditions except aquifers with very high or very low groundwater flow. Slow-release ...

  13. Development of conceptual groundwater flow model for Pali Area ...

    African Journals Online (AJOL)

    use

    be accelerated due to climate change (Mall et al., 2006). Groundwater ... experiencing groundwater pollution problem due to rapid industrialization ... LITERATURE REVIEW ... the impact of a proposed action on existing conditions of ..... Water Air. Soil Pollut., 128: 369-389. Gurunadha Rao VVS, Thangarajan M (1999).

  14. Groundwater sustainability strategies

    Science.gov (United States)

    Gleeson, Tom; VanderSteen, Jonathan; Sophocleous, Marios A.; Taniguchi, Makoto; Alley, William M.; Allen, Diana M.; Zhou, Yangxiao

    2010-01-01

    Groundwater extraction has facilitated significant social development and economic growth, enhanced food security and alleviated drought in many farming regions. But groundwater development has also depressed water tables, degraded ecosystems and led to the deterioration of groundwater quality, as well as to conflict among water users. The effects are not evenly spread. In some areas of India, for example, groundwater depletion has preferentially affected the poor. Importantly, groundwater in some aquifers is renewed slowly, over decades to millennia, and coupled climate–aquifer models predict that the flux and/or timing of recharge to many aquifers will change under future climate scenarios. Here we argue that communities need to set multigenerational goals if groundwater is to be managed sustainably.

  15. Dynamics of Agricultural Groundwater Extraction

    NARCIS (Netherlands)

    Hellegers, P.J.G.J.; Zilberman, D.; Ierland, van E.C.

    2001-01-01

    Agricultural shallow groundwater extraction can result in desiccation of neighbouring nature reserves and degradation of groundwater quality in the Netherlands, whereas both externalities are often not considered when agricultural groundwater extraction patterns are being determined. A model is

  16. Groundwater management institutions to protect riparian habitat

    Science.gov (United States)

    Orr, Patricia; Colby, Bonnie

    2004-12-01

    Groundwater pumping affects riparian habitat when it causes the water table to drop beyond the reach of riparian plants. Riparian habitat provides services that are not directly traded in markets, as is the case with many environmental amenities. There is no direct market where one may buy or sell the mix of services provided by a riparian corridor. The objective of this article is to review groundwater management mechanisms and assess their strengths and weaknesses for preserving the ecological integrity of riparian areas threatened by groundwater pumping. Policy instruments available to those concerned with the effects of groundwater pumping on riparian areas fall into three broad categories: (1) command and control (CAC), (2) incentive-based economic instruments, and (3) cooperative/suasive strategies. The case of the San Pedro River illustrates multiple and overlapping strategies applied in an ongoing attempt to reverse accumulating damage to a riparian ecosystem. Policy makers in the United States can choose among a broad menu of policy options to protect riparian habitat from groundwater pumping. They can capitalize on the clarity of command-and-control strategies, the flexibility and less obtrusive nature of incentive-based economic strategies, and the benefits that collaborative efforts can bring in the form of mutual consideration. While collaborative problem solving and market-based instruments are important policy tools, experience indicates that a well-formulated regulatory structure to limit regional groundwater pumping is an essential component of an effective riparian protection strategy.

  17. Modeling of magneto-mechanical response of magnetorheological elastomers (MRE) and MRE-based systems: a review

    Science.gov (United States)

    Asun Cantera, M.; Behrooz, Majid; Gibson, Ronald F.; Gordaninejad, Faramarz

    2017-02-01

    This article is a review of models that capture the magneto-mechanical response of magnetorheological elastomers (MREs) and MRE-based systems. Where available, experimental validations of models are also discussed. The models are categorized as either particle interaction-based, magnetoelastic response-based, magnetoviscoelastic response-based, or models including the effects of environmental conditions and fatigue. Analytical, numerical, finite element, and phenomenological investigations that explore changes in stiffness and damping of anisotropic MREs are reviewed. Phenomenological models of MRE systems used in different applications are also examined.

  18. Review of Groundwater-Surface Water Interactions in Wetland%湿地地表水—地下水交互作用的研究综述

    Institute of Scientific and Technical Information of China (English)

    范伟; 章光新; 李然然

    2012-01-01

    impacts on hydrological and water supply regimes,which will in turn impose additional pressures on wetland.Subsequently the interactions among multi-interfaces integrating physical,chemical and biological processes will be enhanced for better understanding under changing conditions,and it is supposed to be counteractive to the SW-GW system extensively indeed.Concerted efforts from multidisciplinary approaches must be encouraged to elucidate the different interfaces effects,which help to understand the eco-environmental response to SW-GW interactions and provide insight into the research methodologies in return,because the interfaces effects display a function of fingerprinting to the characteristics of the interactions.Finally,the SW-GW interactions models are reviewed,and it is important to note that the models of SW-GW interactions coupling the water quantity and quality should be constructed based upon the understanding of hydrologic characteristics in wetland.To identify the information on different scales,coupling several mechanisms and verifying the parameters in the model are the key points in future study.Overall,the SW-GW interactions strongly influence the spatial/ temporal availability of the water resources and the structure/ function of the wetland ecosystem.Therefore,further study will be necessary to help water resources managers to deal with such issues as fiood mitigation,groundwater exploitation,and biodiversity conservation in a more integrated and sustainable manner.

  19. Anatomy of Student Models in Adaptive Learning Systems: A Systematic Literature Review of Individual Differences from 2001 to 2013

    Science.gov (United States)

    Nakic, Jelena; Granic, Andrina; Glavinic, Vlado

    2015-01-01

    This study brings an evidence-based review of user individual characteristics employed as sources of adaptation in recent adaptive learning systems. Twenty-two user individual characteristics were explored in a systematically designed search procedure, while 17 of them were identified as sources of adaptation in final selection. The content…

  20. Hallucinogen persisting perception disorder and the serotonergic system : A comprehensive review including new MDMA-related clinical cases

    NARCIS (Netherlands)

    Litjens, Ruud P W; Brunt, Tibor M.; Alderliefste, Gerard Jan; Westerink, Remco H S|info:eu-repo/dai/nl/239425952

    2014-01-01

    Hallucinogen persisting perception disorder (HPPD) is a drug-induced condition associated with inaccurate visual representations. Since the underlying mechanism(s) are largely unknown, this review aims to uncover aspects underlying its etiology. Available evidence on HPPD and drug-related altered vi

  1. Hallucinogen persisting perception disorder and the serotonergic system : A comprehensive review including new MDMA-related clinical cases

    NARCIS (Netherlands)

    Litjens, Ruud P W; Brunt, Tibor M.; Alderliefste, Gerard Jan; Westerink, Remco H S

    2014-01-01

    Hallucinogen persisting perception disorder (HPPD) is a drug-induced condition associated with inaccurate visual representations. Since the underlying mechanism(s) are largely unknown, this review aims to uncover aspects underlying its etiology. Available evidence on HPPD and drug-related altered vi

  2. Human health and groundwater

    Science.gov (United States)

    The high quality of most groundwaters, consequent upon the self-purification capacity of subsurface strata, has long been a key factor in human health and wellbeing. More than 50% of the world’s population now rely on groundwater for their supply of drinking water – and in most circumstances a prope...

  3. Groundwater and Distribution Workbook.

    Science.gov (United States)

    Ekman, John E.

    Presented is a student manual designed for the Wisconsin Vocational, Technical and Adult Education Groundwater and Distribution Training Course. This program introduces waterworks operators-in-training to basic skills and knowledge required for the operation of a groundwater distribution waterworks facility. Arranged according to the general order…

  4. Building groundwater modeling capacity in Mongolia

    Science.gov (United States)

    Valder, Joshua F.; Carter, Janet M.; Anderson, Mark T.; Davis, Kyle W.; Haynes, Michelle A.; Dorjsuren Dechinlhundev,

    2016-06-16

    Ulaanbaatar, the capital city of Mongolia (fig. 1), is dependent on groundwater for its municipal and industrial water supply. The population of Mongolia is about 3 million people, with about one-half the population residing in or near Ulaanbaatar (World Population Review, 2016). Groundwater is drawn from a network of shallow wells in an alluvial aquifer along the Tuul River. Evidence indicates that current water use may not be sustainable from existing water sources, especially when factoring the projected water demand from a rapidly growing urban population (Ministry of Environment and Green Development, 2013). In response, the Government of Mongolia Ministry of Environment, Green Development, and Tourism (MEGDT) and the Freshwater Institute, Mongolia, requested technical assistance on groundwater modeling through the U.S. Army Corps of Engineers (USACE) to the U.S. Geological Survey (USGS). Scientists from the USGS and USACE provided two workshops in 2015 to Mongolian hydrology experts on basic principles of groundwater modeling using the USGS groundwater modeling program MODFLOW-2005 (Harbaugh, 2005). The purpose of the workshops was to bring together representatives from the Government of Mongolia, local universities, technical experts, and other key stakeholders to build in-country capacity in hydrogeology and groundwater modeling.A preliminary steady-state groundwater-flow model was developed as part of the workshops to demonstrate groundwater modeling techniques to simulate groundwater conditions in alluvial deposits along the Tuul River in the vicinity of Ulaanbaatar. ModelMuse (Winston, 2009) was used as the graphical user interface for MODFLOW for training purposes during the workshops. Basic and advanced groundwater modeling concepts included in the workshops were groundwater principles; estimating hydraulic properties; developing model grids, data sets, and MODFLOW input files; and viewing and evaluating MODFLOW output files. A key to success was

  5. Creating a Patient-Centered Health Care Delivery System: A Systematic Review of Health Care Quality From the Patient Perspective.

    Science.gov (United States)

    Mohammed, Khaled; Nolan, Margaret B; Rajjo, Tamim; Shah, Nilay D; Prokop, Larry J; Varkey, Prathibha; Murad, Mohammad H

    2016-01-01

    Patient experience is one of key domains of value-based purchasing that can serve as a measure of quality and be used to improve the delivery of health services. The aims of this study are to explore patient perceptions of quality of health care and to understand how perceptions may differ by settings and condition. A systematic review of multiple databases was conducted for studies targeting patient perceptions of quality of care. Two reviewers screened and extracted data independently. Data synthesis was performed following a meta-narrative approach. A total of 36 studies were included that identified 10 quality dimensions perceived by patients: communication, access, shared decision making, provider knowledge and skills, physical environment, patient education, electronic medical record, pain control, discharge process, and preventive services. These dimensions can be used in planning and evaluating health care delivery. Future research should evaluate the effect of interventions targeting patient experience on patient outcomes.

  6. Groundwater Recharge, Evapotranspiration and Surface Runoff ...

    African Journals Online (AJOL)

    Bheema

    Department of Earth Science, CNCS, P.O. Box 231, Mekelle University, ... The mean annual groundwater recharge, evapotranspiration and runoff were ... Accordingly, recharge accounts for 12% of the precipitation .... So, to apply the WetSpass for Illala catchment, input of the meteorological grid map ..... Review of Australian.

  7. Trends in groundwater quality in relation to groundwater age

    NARCIS (Netherlands)

    Visser, A.

    2009-01-01

    Groundwater is a valuable natural resource and as such should be protected from chemical pollution. Because of the long travel times of pollutants through groundwater bodies, early detection of groundwater quality deterioration is necessary to efficiently protect groundwater bodies. The aim of this

  8. Trends in groundwater quality in relation to groundwater age

    NARCIS (Netherlands)

    Visser, A.

    2009-01-01

    Groundwater is a valuable natural resource and as such should be protected from chemical pollution. Because of the long travel times of pollutants through groundwater bodies, early detection of groundwater quality deterioration is necessary to efficiently protect groundwater bodies. The aim of this

  9. Genesis and transport of hexavalent chromium in the system ophiolitic rocks - groundwater

    Science.gov (United States)

    Shchegolikhina, Anastasia; Guadagnini, Laura; Guadagnini, Alberto

    2015-04-01

    Our study aims at contributing to the quantification and characterization of chromium transport processes from host rocks and soil matrices to groundwater. We focus on dissolved hexavalent chromium detected in groundwaters of geological regions with ophiolitic rocks (ophiolites and serpentinites) inclusions due to its critical ecological impact. (Oze et al., 2004). Despite the large number of analyses on the occurrence of high concentrations of hazardous hexavalent chromium ions in natural waters, only few studies were performed with the objective of identifying and investigating the geochemical reactions which could occur in the natural system rock - groundwater - dissolved chromium (Fantoni et al., 2002, Stephen and James, 2004, Lelli et al., 2013). In this context, there is a need for integration of results obtained from diverse studies in various regions and settings to improve our knowledge repository. Our theoretical analyses are grounded and driven by practical scenarios detected in subsurface reservoirs exploited for civil and industrial use located in the Emilia-Romagna region (Italy). Available experimental datasets are complemented with data from other international regional-scale settings (Altay mountains region, Russia). Modeling of chromium transformation and migration particularly includes characterization of the multispecies geochemical system. A key aspect of our study is the analysis of the complex competitive sorption processes governing heavy metal evolution in groundwater. The results of the research allow assessing the critical qualitative features of the mechanisms of hexavalent chromium ion mobilization from host rocks and soils and the ensuing transformation and migration to groundwater under the influence of diverse environmental factors. The study is then complemented by the quantification of the main sources of uncertainty associated with prediction of heavy metal contamination levels in the groundwater system explored. Fantoni, D

  10. Integrated methodological frameworks for modelling agent-based advanced supply chain planning systems: A systematic literature review

    Directory of Open Access Journals (Sweden)

    Luis Antonio Santa-Eulalia

    2011-12-01

    Full Text Available Purpose: The objective of this paper is to provide a systematic literature review of recent developments in methodological frameworks for the modelling and simulation of agent-based advanced supply chain planning systems.Design/methodology/approach: A systematic literature review is provided to identify, select and make an analysis and a critical summary of all suitable studies in the area. It is organized into two blocks: the first one covers agent-based supply chain planning systems in general terms, while the second one specializes the previous search to identify those works explicitly containing methodological aspects.Findings: Among sixty suitable manuscripts identified in the primary literature search, only seven explicitly considered the methodological aspects. In addition, we noted that, in general, the notion of advanced supply chain planning is not considered unambiguously, that the social and individual aspects of the agent society are not taken into account in a clear manner in several studies and that a significant part of the works are of a theoretical nature, with few real-scale industrial applications. An integrated framework covering all phases of the modelling and simulation process is still lacking in the literature visited.Research limitations/implications: The main research limitations are related to the period covered (last four years, the selected scientific databases, the selected language (i.e. English and the use of only one assessment framework for the descriptive evaluation part.Practical implications: The identification of recent works in the domain and discussion concerning their limitations can help pave the way for new and innovative researches towards a complete methodological framework for agent-based advanced supply chain planning systems.Originality/value: As there are no recent state-of-the-art reviews in the domain of methodological frameworks for agent-based supply chain planning, this paper contributes to

  11. Current and future prospects for heat recovery from waste in European district heating systems: A literature and data review

    DEFF Research Database (Denmark)

    Persson, Urban; Münster, Marie

    2016-01-01

    Municipal solid waste has seen increasing annual volumes for many decades in contemporary Europe and constitutes, if not properly managed, an environmental problem due to local pollution and greenhouse gas emissions. From an energy perspective, waste is also an alternative fuel for power and heat...... heat distribution infrastructures, without which no large-scale recovery and utilisation of excess heat is possible. In this paper, which aims to estimate municipal solid waste volumes available for heat recovery in European district heating systems in 2030, a literature and data review is performed...

  12. The Development of Sustainable Saltwater-Based Food Production Systems: A Review of Established and Novel Concepts

    Directory of Open Access Journals (Sweden)

    Daryl Gunning

    2016-12-01

    Full Text Available The demand for seafood products on the global market is rising, particularly in Asia, as affluence and appreciation of the health benefits of seafood increase. This is coupled with a capture fishery that, at best, is set for stagnation and, at worst, significant collapse. Global aquaculture is the fastest growing sector of the food industry and currently accounts for approximately 45.6% of the world’s fish consumption. However, the rapid development of extensive and semi-extensive systems, particularly intensive marine-fed aquaculture, has resulted in worldwide concern about the potential environmental, economic, and social impacts of such systems. In recent years, there has been a significant amount of research conducted on the development of sustainable saltwater-based food production systems through mechanical (e.g., recirculatory aquaculture (RAS systems methods and ecosystem-based approaches (e.g., integrated multi-trophic aquaculture (IMTA. This review article will examine the potential negative impacts of monocultural saltwater aquaculture operations and review established (RAS and novel (IMTA; constructed wetlands; saltwater aquaponics saltwater-based food production systems and discuss their (potential contribution to the development of sustainable and environmentally-friendly systems.

  13. Hydatid disease of the central nervous system: a review of literature with an emphasis on Latin American countries.

    Science.gov (United States)

    Nourbakhsh, Ali; Vannemreddy, Prasad; Minagar, Alireza; Toledo, Eduardo González; Palacios, Enrique; Nanda, Anil

    2010-04-01

    To provide an up to date review of the epidemiology, etiology, treatment and prevention of hydatid cyst of the central nervous system, with an emphasis in South American countries. We searched the PubMed databases for articles containing the terms 'hydatid cyst' and 'nervous system'. We found and reviewed 303 articles and their related references. We provide the available information on the pathology, life cycle and diagnostic modalities (laboratory tests and imaging) along with possible complications of the disease. Current treatment methods of hydatid cyst in the brain and spine are also being discussed. Echinococcosis is a rare parasitic disease, endemic in some parts of South America. The epidemiology of echinococcosis is influenced by agricultural, educational, economic, medical and cultural factors. Human infestation occurs through the fecal-oral route. Infection of the central nervous system is rare, and the mainstay of treatment is surgical excision of the intracranial or spinal cyst, when present. Preventive programs should break the parasite life cycle and also educate the farmers in endemic areas.

  14. Vaccinations in migrants and refugees: a challenge for European health systems. A systematic review of current scientific evidence.

    Science.gov (United States)

    Mipatrini, Daniele; Stefanelli, Paola; Severoni, Santino; Rezza, Giovanni

    2017-03-01

    The decline of immunization rates in countries of origin of migrants and refugees, along with risky conditions during the journey to Europe, may threaten migrants' health. We performed a systematic review of the scientific literature in order to assess the frequency of vaccine preventable diseases, and vaccination coverage among migrants and refugees in Europe. To this end, Medline and Cochrane databases were considered. After the screening and the selection process, 58 papers were included in the review. We focused on the following vaccine-preventable diseases: hepatitis B, measles, rubella, mumps, tetanus, poliomyelitis, pertussis, diphtheria, meningitis, and varicella. The results were presented as a qualitative synthesis. In summary, several studies highlighted that migrants and refugees have lower immunization rates compared to European-born individuals. Firstly, this is due to low vaccination coverage in the country of origin. Then, several problems may limit migrants' access to vaccination in Europe: (i) migrants are used to move around the continent, and many vaccines require multiple doses at regular times; (ii) information on the immunization status of migrants is often lacking; (iii) hosting countries face severe economic crises; (iv) migrants often refuse registration with medical authorities for fear of legal consequences and (v) the lack of coordination among public health authorities of neighboring countries may determine either duplications or lack of vaccine administration. Possible strategies to overcome these problems include tailoring immunization services on the specific needs of the target population, developing strong communication campaigns, developing vaccination registers, and promoting collaboration among public health authorities of European Countries.

  15. Global depletion of groundwater resources

    NARCIS (Netherlands)

    Wada, Y.; Beek, L.P.H. van; van Kempen, C.M.; Reckman, J.W.T.M.; Vasak, S.; Bierkens, M.F.P.

    2010-01-01

    In regions with frequent water stress and large aquifer systems groundwater is often used as an additional water source. If groundwater abstraction exceeds the natural groundwater recharge for extensive areas and long times, overexploitation or persistent groundwater depletion occurs. Here we provid

  16. Ground-water quality in Geauga County, Ohio; review of previous studies, status in 1999, and comparison of 1986 and 1999 data

    Science.gov (United States)

    Jagucki, Martha L.; Darner, Robert A.

    2001-01-01

    Most residents in Geauga County, Ohio, rely on ground water as their primary source of drinking water. With population growing at a steady rate, the possibility that human activity will affect ground-water quality becomes considerable. This report presents the results of a study by the U.S. Geological Survey (USGS), in cooperation with the Geauga County Planning Commission and Board of County Commissioners, to provide a brief synopsis of work previously done within the county, to assess the present (1999) ground-water quality, and to determine any changes in ground-water quality between 1986 and 1999. Previous studies of ground-water quality in the county have consistently reported that manganese and iron concentrations in ground water in Geauga County often exceed the U.S. Environmental Protection Agency (USEPA) Secondary Maximum Contaminant Level (SMCL). Road salt and, less commonly, oil-field brines and volatile organic compounds (VOCs) have been found in ground water at isolated locations. Nitrate has not been detected above the USEPA Maximum Contaminant Level (MCL) of 10 milligrams per liter as N; however, nitrate has been found in some locations at levels that may indicate the effects of fertilizer application or effluent from septic systems. Between June 7 and July 1, 1999, USGS personnel collected a total of 31 water-quality samples from wells completed in glacial deposits, the Pottsville Formation, the Cuyahoga Group, and the Berea Sandstone. All samples were analyzed for VOCs, sulfide, dissolved organic carbon, major ions, trace elements, alkalinity, total coliforms, and Escherichia coli bacteria. Fourteen of the samples also were analyzed for tritium. Water-quality data were used to determine (1) suitability of water for drinking, (2) age of ground water, (3) stratigraphic variation in water quality, (4) controls on water quality, and (5) temporal variation in water quality. Water from 16 of the 31 samples exceeded the Geauga County General Health

  17. Occupational musculoskeletal and mental health: Significance of rationalization and opportunities to create sustainable production systems - A systematic review.

    Science.gov (United States)

    Westgaard, R H; Winkel, J

    2011-01-01

    This literature review aims to identify occupational musculoskeletal and mental health effects of production system rationalization as well as organizational-level measures that may improve health outcome ("modifiers" in this review). A short review of the effect of ergonomic interventions is included as background and rationalization is discussed as a theoretical concept. Indicator variables for occupational musculoskeletal and mental health and related risk factors are presented. Variables with a generalized format were allowed in the literature searches (e.g., job satisfaction and absenteeism were accepted as risk factor and health indicator, respectively), suitable for the research fields of work sociology, organization science, human resource management (HRM) and economics research. One hundred and sixty-two studies of rationalization effects on health and risk factors and 72 organization-level modifier results were accepted into the final database. Entries were sorted by rationalization strategy and work life sector, and trends in outcome (positive, mixed, no effect, or negative effect on health and risk factors) were determined. Rationalizations have a dominant negative effect on health and risk factors (57% negative, 19% positive); the most negative effects were found for downsizing and restructuring rationalizations in general (71 studies negative, 13 positive) and for the health care sector in particular (36 studies negative, 2 positive). The rationalization strategy High Performance Work System (HPWS) was associated with the highest fraction positive outcome studies (6 of 10 studies). Other rationalization strategies (lean practices, parallel vs. serial production and mechanization level) reported intermediate results, in part dependent on work life sector, but also on the year when studies were carried out. Worker participation, resonant management style, information, support, group autonomy and procedural justice were modifiers with favourable

  18. Groundwater data network interoperability

    Science.gov (United States)

    Brodaric, Boyan; Booth, Nathaniel; Boisvert, Eric; Lucido, Jessica M.

    2016-01-01

    Water data networks are increasingly being integrated to answer complex scientific questions that often span large geographical areas and cross political borders. Data heterogeneity is a major obstacle that impedes interoperability within and between such networks. It is resolved here for groundwater data at five levels of interoperability, within a Spatial Data Infrastructure architecture. The result is a pair of distinct national groundwater data networks for the United States and Canada, and a combined data network in which they are interoperable. This combined data network enables, for the first time, transparent public access to harmonized groundwater data from both sides of the shared international border.

  19. Groundwater contamination in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Tase, Norio [Univ. of Tsukuba, Ibaraki (Japan)

    1992-07-01

    Problems on groundwater contamination in Japan are briefly summarized in this paper. Although normal physical conditions in Japan restrict the possibilities of groundwater contamination, human activities are threatening groundwater resources. A survey by the Environment Agency of Japan showed nationwide spreading of organic substances, such as trichloroethylene as well as nitrogen compounds. Synthetic detergents have also been detected even in rural areas and in deep confined aquifers, although their concentrations are not as high. Public awareness of agrichemical or pesticides abuse, especially from golf courses, is apparent. Other problems such as nitrate-nitrogen, leachate from landfills, and the leaking of underground storage tanks are also discussed. 9 refs., 3 figs., 4 tabs.

  20. Groundwater contamination in Japan

    Science.gov (United States)

    Tase, Norio

    1992-07-01

    Problems on groundwater contamination in Japan are briefly summarized in this paper. Although normal physical conditions in Japan restrict the possibilities of groundwater contamination, human activities are threatening groundwater resources. A survey by the Environment Agency of Japan showed nationwide spreading of organic substances, such as trichloroethylene as well as nitrogen compounds. Synthetic detergents have also been detected even in rural areas and in deep confined aquifers, although their concentrations are not as high. Public awareness of agrichemical or pesticides abuse, especially from golf courses, is apparent. Other problems such as nitrate-nitrogen, leachate from landfills, and the leaking of underground storage tanks are also discussed.

  1. Behavior of reoccurring PARAFAC components in fluorescent dissolved organic matter in natural and engineered systems: a critical review.

    Science.gov (United States)

    Ishii, Stephanie K L; Boyer, Treavor H

    2012-02-21

    Fluorescence spectroscopy coupled with parallel factor analysis (PARAFAC) has been widely used to characterize dissolved organic matter (DOM). Characterization is based on the intensity and location of independent fluorescent components identified in models constructed from excitation-emission matrices (EEMs). Similar fluorescent components have been identified in PARAFAC studies across a wide range of systems; however, there is a lack of discussion regarding the consistency with which these similar components behave. The overall goal of this critical review is to compare results for PARAFAC studies published since the year 2000 which include one or more of three reoccurring humic-like components. Components are compared and characterized based on EEM location, characteristic ecosystems, and behavior in natural and engineered systems. This synthesis allows PARAFAC users to more confidently infer DOM characteristics based on identified components. Additionally, behavioral inconsistencies between similar components help elucidate DOM properties for which fluorescence spectroscopy with PARAFAC may be a weak predictive tool.

  2. Roles of microorganisms other than Clostridium and Enterobacter in anaerobic fermentative biohydrogen production systems--a review.

    Science.gov (United States)

    Hung, Chun-Hsiung; Chang, Yi-Tang; Chang, Yu-Jie

    2011-09-01

    Anaerobic fermentative biohydrogen production, the conversion of organic substances especially from organic wastes to hydrogen gas, has become a viable and promising means of producing sustainable energy. Successful biological hydrogen production depends on the overall performance (results of interactions) of bacterial communities, i.e., mixed cultures in reactors. Mixed cultures might provide useful combinations of metabolic pathways for the processing of complex waste material ingredients, thereby supporting the more efficient decomposition and hydrogenation of biomass than pure bacteria species would. Therefore, understanding the relationships between variations in microbial composition and hydrogen production efficiency is the first step in constructing more efficient hydrogen-producing consortia, especially when complex and non-sterilized organic wastes are used as feeding substrates. In this review, we describe recent discoveries on bacterial community composition obtained from dark fermentation biohydrogen production systems, with emphasis on the possible roles of microorganisms that co-exist with common hydrogen producers.

  3. A national program for energy-efficient mortgages and home energy rating systems: A blueprint for action. Review draft

    Energy Technology Data Exchange (ETDEWEB)

    1992-03-01

    This Review Draft reports findings and recommendations of the National Collaborative on Home Energy Rating Systems and Mortgage Incentives for Energy Efficiency. The US Department of Energy, in cooperation with the US Department of Housing and Urban Development, formed this National Collaborative as a National Energy Strategy initiative. Participating in the Collaborative were representatives of the primary and secondary mortgage markets, builder and remodeler organizations, real estate and appraiser associations, the home energy rating system industry, utility associations, consumer and public interest groups, state and local government interest groups, and environmental organizations. The Collaborative`s purpose was to develop a voluntary national program encouraging energy efficiency in homes through mortgage incentives linked to home energy ratings.

  4. Prognostic and health management for engineering systems: a review of the data-driven approach and algorithms

    Directory of Open Access Journals (Sweden)

    Thamo Sutharssan

    2015-07-01

    Full Text Available Prognostics and health management (PHM has become an important component of many engineering systems and products, where algorithms are used to detect anomalies, diagnose faults and predict remaining useful lifetime (RUL. PHM can provide many advantages to users and maintainers. Although primary goals are to ensure the safety, provide state of the health and estimate RUL of the components and systems, there are also financial benefits such as operational and maintenance cost reductions and extended lifetime. This study aims at reviewing the current status of algorithms and methods used to underpin different existing PHM approaches. The focus is on providing a structured and comprehensive classification of the existing state-of-the-art PHM approaches, data-driven approaches and algorithms.

  5. Improving clinical practice using clinical decision support systems: a systematic review of trials to identify features critical to success

    Science.gov (United States)

    Kawamoto, Kensaku; Houlihan, Caitlin A; Balas, E Andrew; Lobach, David F

    2005-01-01

    Objective To identify features of clinical decision support systems critical for improving clinical practice. Design Systematic review of randomised controlled trials. Data sources Literature searches via Medline, CINAHL, and the Cochrane Controlled Trials Register up to 2003; and searches of reference lists of included studies and relevant reviews. Study selection Studies had to evaluate the ability of decision support systems to improve clinical practice. Data extraction Studies were assessed for statistically and clinically significant improvement in clinical practice and for the presence of 15 decision support system features whose importance had been repeatedly suggested in the literature. Results Seventy studies were included. Decision support systems significantly improved clinical practice in 68% of trials. Univariate analyses revealed that, for five of the system features, interventions possessing the feature were significantly more likely to improve clinical practice than interventions lacking the feature. Multiple logistic regression analysis identified four features as independent predictors of improved clinical practice: automatic provision of decision support as part of clinician workflow (P < 0.00001), provision of recommendations rather than just assessments (P = 0.0187), provision of decision support at the time and location of decision making (P = 0.0263), and computer based decision support (P = 0.0294). Of 32 systems possessing all four features, 30 (94%) significantly improved clinical practice. Furthermore, direct experimental justification was found for providing periodic performance feedback, sharing recommendations with patients, and requesting documentation of reasons for not following recommendations. Conclusions Several features were closely correlated with decision support systems' ability to improve patient care significantly. Clinicians and other stakeholders should implement clinical decision support systems that incorporate these

  6. Direct Nitrous Oxide Emissions From Tropical And Sub-Tropical Agricultural Systems - A Review And Modelling Of Emission Factors

    Science.gov (United States)

    Albanito, Fabrizio; Lebender, Ulrike; Cornulier, Thomas; Sapkota, Tek B.; Brentrup, Frank; Stirling, Clare; Hillier, Jon

    2017-03-01

    There has been much debate about the uncertainties associated with the estimation of direct and indirect agricultural nitrous oxide (N2O) emissions in developing countries and in particular from tropical regions. In this study, we report an up-to-date review of the information published in peer-review journals on direct N2O emissions from agricultural systems in tropical and sub-tropical regions. We statistically analyze net-N2O-N emissions to estimate tropic-specific annual N2O emission factors (N2O-EFs) using a Generalized Additive Mixed Model (GAMM) which allowed the effects of multiple covariates to be modelled as linear or smooth non-linear continuous functions. Overall the mean N2O-EF was 1.2% for the tropics and sub-tropics, thus within the uncertainty range of IPCC-EF. On a regional basis, mean N2O-EFs were 1.4% for Africa, 1.1%, for Asia, 0.9% for Australia and 1.3% for Central & South America. Our annual N2O-EFs, estimated for a range of fertiliser rates using the available data, do not support recent studies hypothesising non-linear increase N2O-EFs as a function of applied N. Our findings highlight that in reporting annual N2O emissions and estimating N2O-EFs, particular attention should be paid in modelling the effect of study length on response of N2O.

  7. Groundwater sustainability and urban development - a major challenge for the 21st century

    Science.gov (United States)

    Foster, Stephen

    2016-04-01

    Groundwater is a critical, but often under appreciated, resource for urban water supply, a serious and costly hazard to urban infrastructure, and the 'invisible link' between various facets of the urbanisation process. An overview is presented of the benefits of urban groundwater use, together with some insidious and persistent problems that groundwater can present (especially those related to groundwater pollution from inadequate sanitation) for urban development. Spontaneous piecemeal approaches invariably mean that 'one person's solution becomes another person's problem' - and there is a strong argument for groundwater considerations to be part of a more holistic approach to urban infrastructure planning and management. However this is not a simple task because of the widespread vacuum of institutional responsibility and accountability for groundwater in urban areas. The current state of urban groundwater management will be reviewed, and pragmatic solutions to strengthening various facets of urban groundwater governance and management presented, using examples from Latin America and South Asia.

  8. Groundwater recharge from point to catchment scale

    Science.gov (United States)

    Leterme, Bertrand; Di Ciacca, Antoine; Laloy, Eric; Jacques, Diederik

    2016-04-01

    Accurate estimation of groundwater recharge is a challenging task as only a few devices (if any) can measure it directly. In this study, we discuss how groundwater recharge can be calculated at different temporal and spatial scales in the Kleine Nete catchment (Belgium). A small monitoring network is being installed, that is aimed to monitor the changes in dominant processes and to address data availability as one goes from the point to the catchment scale. At the point scale, groundwater recharge is estimated using inversion of soil moisture and/or water potential data and stable isotope concentrations (Koeniger et al. 2015). At the plot scale, it is proposed to monitor the discharge of a small drainage ditch in order to calculate the field groundwater recharge. Electrical conductivity measurements are necessary to separate shallow from deeper groundwater contribution to the ditch discharge (see Di Ciacca et al. poster in session HS8.3.4). At this scale, two or three-dimensional process-based vadose zone models will be used to model subsurface flow. At the catchment scale though, using a mechanistic, process-based model to estimate groundwater recharge is debatable (because of, e.g., the presence of numerous drainage ditches, mixed land use pixels, etc.). We therefore investigate to which extent various types of surrogate models can be used to make the necessary upscaling from the plot scale to the scale of the whole Kleine Nete catchment. Ref. Koeniger P, Gaj M, Beyer M, Himmelsbach T (2015) Review on soil water isotope based groundwater recharge estimations. Hydrological Processes, DOI: 10.1002/hyp.10775

  9. Canada's groundwater resources

    National Research Council Canada - National Science Library

    Rivera, Alfonso

    2014-01-01

    Groundwater is essential for life in arid and semiarid region. It is also important in humid regions, and is one of the fundamental requirements for the maintenance of natural landscapes and aquatic ecosystem...

  10. Groundwater Capture Zones

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Source water protection areas are delineated for each groundwater-based public water supply system using available geologic and hydrogeologic information to...

  11. The communication of forensic science in the criminal justice system: A review of theory and proposed directions for research.

    Science.gov (United States)

    Howes, Loene M

    2015-03-01

    Clear communication about forensic science is essential to the effectiveness and perceived trustworthiness of the criminal justice system. Communication can be seen as a meaning-making process that involves different components such as the sender of a message, the message itself, the channel in which a message is sent, and the receiver of the message. Research conducted to date on the communication between forensic scientists and non-scientists in the criminal justice system has focused on different components of the communication process as objects of study. The purpose of this paper is to bring together communication theory and past research on the communication of forensic science to contribute to a deeper understanding of it, and to provide a coherent view of it overall. The paper first outlines the broader context of communication theory and science communication as a backdrop to forensic science communication. Then it presents a conceptual framework as a way to organise past research and, using the framework, reviews recent examples of empirical research and commentary on the communication of forensic science. Finally the paper identifies aspects of the communication of forensic science that may be addressed by future research to enhance the effectiveness of communication between scientists and non-scientists in this multidisciplinary arena.

  12. Care and feeding of the endocannabinoid system: a systematic review of potential clinical interventions that upregulate the endocannabinoid system.

    Directory of Open Access Journals (Sweden)

    John M McPartland

    Full Text Available BACKGROUND: The "classic" endocannabinoid (eCB system includes the cannabinoid receptors CB1 and CB2, the eCB ligands anandamide (AEA and 2-arachidonoylglycerol (2-AG, and their metabolic enzymes. An emerging literature documents the "eCB deficiency syndrome" as an etiology in migraine, fibromyalgia, irritable bowel syndrome, psychological disorders, and other conditions. We performed a systematic review of clinical interventions that enhance the eCB system--ways to upregulate cannabinoid receptors, increase ligand synthesis, or inhibit ligand degradation. METHODOLOGY/PRINCIPAL FINDINGS: We searched PubMed for clinical trials, observational studies, and preclinical research. Data synthesis was qualitative. Exclusion criteria limited the results to 184 in vitro studies, 102 in vivo animal studies, and 36 human studies. Evidence indicates that several classes of pharmaceuticals upregulate the eCB system, including analgesics (acetaminophen, non-steroidal anti-inflammatory drugs, opioids, glucocorticoids, antidepressants, antipsychotics, anxiolytics, and anticonvulsants. Clinical interventions characterized as "complementary and alternative medicine" also upregulate the eCB system: massage and manipulation, acupuncture, dietary supplements, and herbal medicines. Lifestyle modification (diet, weight control, exercise, and the use of psychoactive substances--alcohol, tobacco, coffee, cannabis also modulate the eCB system. CONCLUSIONS/SIGNIFICANCE: Few clinical trials have assessed interventions that upregulate the eCB system. Many preclinical studies point to other potential approaches; human trials are needed to explore these promising interventions.

  13. [Advances in molecular mechanisms of adaptive immunity mediated by type I-E CRISPR/Cas system--A review].

    Science.gov (United States)

    Sun, Dongchang; Qiu, Juanping

    2016-01-01

    To better adapt to the environment, prokaryocyte can take up exogenous genes (from bacteriophages, plasmids or genomes of other species) through horizontal gene transfer. Accompanied by the acquisition of exogenous genes, prokaryocyte is challenged by the invasion of 'selfish genes'. Therefore, to protect against the risk of gene transfer, prokaryocyte needs to establish mechanisms for selectively taking up or degrading exogenous DNA. In recent years, researchers discovered an adaptive immunity, which is mediated by the small RNA guided DNA degradation, prevents the invasion of exogenous genes in prokaryocyte. During the immune process, partial DNA fragments are firstly integrated.to the clustered regularly interspaced short palindromic repeats (CRISPR) located within the genome DNA, and then the mature CRISPR RNA transcript and the CRISPR associated proteins (Cas) form a complex CRISPR/Cas for degrading exogenous DNA. In this review, we will first briefly describe the CRISPR/Cas systems and then mainly focus on the recent advances of the function mechanism and the regulation mechanism of the type I-E CRISPR/Cas system in Escherichia coli.

  14. Analytical methods for soluble microbial products (SMP) and extracellular polymers (ECP) in wastewater treatment systems: a review.

    Science.gov (United States)

    Kunacheva, Chinagarn; Stuckey, David C

    2014-09-15

    Effluents from biological processes contain a wide range of complex organic compounds, including soluble microbial products (SMP) and extracellular polymers (ECP), released during bacteria metabolism in mixed culture in bioreactors. It is important to clearly identify the primary components of SMPs and ECPs in order to understand the fundamental mechanisms of biological activity that create these compounds, and how to reduce these compounds in the effluent. In addition, these compounds constitute the main foulants in membrane bioreactors which are being used more widely around the world. A review on the extraction of ECP, characterization, and identification of SMPs and ECPs is presented, and we summarize up-to-date pretreatments and analytical methods for SMPs. Most researchers have focused more on the overall properties of SMPs and ECPs such as their concentrations, molecular weight distribution, aromaticity, hydrophobic and hydrophilic properties, biodegradability, and toxicity characteristics. Many studies on the identification of effluent SMPs show that most of these compounds were not present in the influent, such as humic acids, polysaccharides, proteins, nucleic acids, organic acids, amino acids, exocellular enzymes, structural components of cells and products of energy metabolism. A few groups of researchers have been working on the identification of compounds in SMPs using advanced analytical techniques such as GC-MS, LC-IT-TOF-MS and MALDI-TOF-MS. However, there is still considerably more work needed to be done analytically to fully understand the chemical characteristics of SMPs and ECPs.

  15. The Impact of Online Social Networks on Health and Health Systems: A Scoping Review and Case Studies.

    Science.gov (United States)

    Griffiths, Frances; Dobermann, Tim; Cave, Jonathan A K; Thorogood, Margaret; Johnson, Samantha; Salamatian, Kavé; Gomez Olive, Francis X; Goudge, Jane

    2015-12-01

    Interaction through online social networks potentially results in the contestation of prevailing ideas about health and health care, and to mass protest where health is put at risk or health care provision is wanting. Through a review of the academic literature and case studies of four social networking health sites (PatientsLikeMe, Mumsnet, Treatment Action Campaign, and My Pro Ana), we establish the extent to which this phenomenon is documented, seek evidence of the prevalence and character of health-related networks, and explore their structure, function, participants, and impact, seeking to understand how they came into being and how they sustain themselves. Results indicate mass protest is not arising from these established health-related networking platforms. There is evidence of changes in policy following campaigning activity prompted by experiences shared through social networking such as improved National Health Service care for miscarriage (a Mumsnet campaign). Platform owners and managers have considerable power to shape these campaigns. Social networking is also influencing health policy indirectly through increasing awareness and so demand for health care. Transient social networking about health on platforms such as Twitter were not included as case studies but may be where the most radical or destabilizing influence on health care policy might arise.

  16. Investigation of Self-Assembly Processes for Chitosan-Based Coagulant-Flocculant Systems: A Mini-Review

    Directory of Open Access Journals (Sweden)

    Savi Bhalkaran

    2016-09-01

    Full Text Available The presence of contaminants in wastewater poses significant challenges to water treatment processes and environmental remediation. The use of coagulation-flocculation represents a facile and efficient way of removing charged particles from water. The formation of stable colloidal flocs is necessary for floc aggregation and, hence, their subsequent removal. Aggregation occurs when these flocs form extended networks through the self-assembly of polyelectrolytes, such as the amine-based polysaccharide (chitosan, which form polymer “bridges” in a floc network. The aim of this overview is to evaluate how the self-assembly process of chitosan and its derivatives is influenced by factors related to the morphology of chitosan (flocculant and the role of the solution conditions in the flocculation properties of chitosan and its modified forms. Chitosan has been used alone or in conjunction with a salt, such as aluminum sulphate, as an aid for the removal of various waterborne contaminants. Modified chitosan relates to grafted anionic or cationic groups onto the C-6 hydroxyl group or the amine group at C-2 on the glucosamine monomer of chitosan. By varying the parameters, such as molecular weight and the degree of deacetylation of chitosan, pH, reaction and settling time, dosage and temperature, self-assembly can be further investigated. This mini-review places an emphasis on the molecular-level details of the flocculation and the self-assembly processes for the marine-based biopolymer, chitosan.

  17. Care and feeding of the endocannabinoid system: a systematic review of potential clinical interventions that upregulate the endocannabinoid system.

    Science.gov (United States)

    McPartland, John M; Guy, Geoffrey W; Di Marzo, Vincenzo

    2014-01-01

    The "classic" endocannabinoid (eCB) system includes the cannabinoid receptors CB1 and CB2, the eCB ligands anandamide (AEA) and 2-arachidonoylglycerol (2-AG), and their metabolic enzymes. An emerging literature documents the "eCB deficiency syndrome" as an etiology in migraine, fibromyalgia, irritable bowel syndrome, psychological disorders, and other conditions. We performed a systematic review of clinical interventions that enhance the eCB system--ways to upregulate cannabinoid receptors, increase ligand synthesis, or inhibit ligand degradation. We searched PubMed for clinical trials, observational studies, and preclinical research. Data synthesis was qualitative. Exclusion criteria limited the results to 184 in vitro studies, 102 in vivo animal studies, and 36 human studies. Evidence indicates that several classes of pharmaceuticals upregulate the eCB system, including analgesics (acetaminophen, non-steroidal anti-inflammatory drugs, opioids, glucocorticoids), antidepressants, antipsychotics, anxiolytics, and anticonvulsants. Clinical interventions characterized as "complementary and alternative medicine" also upregulate the eCB system: massage and manipulation, acupuncture, dietary supplements, and herbal medicines. Lifestyle modification (diet, weight control, exercise, and the use of psychoactive substances--alcohol, tobacco, coffee, cannabis) also modulate the eCB system. Few clinical trials have assessed interventions that upregulate the eCB system. Many preclinical studies point to other potential approaches; human trials are needed to explore these promising interventions.

  18. SYRIAC: The systematic review information automated collection system a data warehouse for facilitating automated biomedical text classification.

    Science.gov (United States)

    Yang, Jianji J; Cohen, Aaron M; Cohen, Aaron; McDonagh, Marian S

    2008-11-06

    Automatic document classification can be valuable in increasing the efficiency in updating systematic reviews (SR). In order for the machine learning process to work well, it is critical to create and maintain high-quality training datasets consisting of expert SR inclusion/exclusion decisions. This task can be laborious, especially when the number of topics is large and source data format is inconsistent.To approach this problem, we build an automated system to streamline the required steps, from initial notification of update in source annotation files to loading the data warehouse, along with a web interface to monitor the status of each topic. In our current collection of 26 SR topics, we were able to standardize almost all of the relevance judgments and recovered PMIDs for over 80% of all articles. Of those PMIDs, over 99% were correct in a manual random sample study. Our system performs an essential function in creating training and evaluation data sets for SR text mining research.

  19. Blood-brain barrier models and their relevance for a successful development of CNS drug delivery systems: a review.

    Science.gov (United States)

    Bicker, Joana; Alves, Gilberto; Fortuna, Ana; Falcão, Amílcar

    2014-08-01

    During the research and development of new drugs directed at the central nervous system, there is a considerable attrition rate caused by their hampered access to the brain by the blood-brain barrier. Throughout the years, several in vitro models have been developed in an attempt to mimic critical functionalities of the blood-brain barrier and reliably predict the permeability of drug candidates. However, the current challenge lies in developing a model that retains fundamental blood-brain barrier characteristics and simultaneously remains compatible with the high throughput demands of pharmaceutical industries. This review firstly describes the roles of all elements of the neurovascular unit and their influence on drug brain penetration. In vitro models, including non-cell based and cell-based models, and in vivo models are herein presented, with a particular emphasis on their methodological aspects. Lastly, their contribution to the improvement of brain drug delivery strategies and drug transport across the blood-brain barrier is also discussed.

  20. Westerly wind events in the tropical Pacific and their influence on the coupled ocean-atmosphere system: A review

    Science.gov (United States)

    Lengaigne, Matthieu; Boulanger, Jean-Philippe; Menkes, Christophe; Delecluse, Pascale; Slingo, Julia

    Observational and modeling aspects about Westerly Wind Events (WWEs) and their influence on the tropical Pacific ocean-atmosphere system are reviewed. WWEs are a large part of the intraseasonal zonal wind activity over the warm pool. They have typical amplitudes of 7 m s-1, zonal width of 20° longitude and duration of about 8 days. Their root causes are often a combination of various factors including the Madden-Julian Oscillation, cold surges from mid-latitudes, tropical cyclones and other mesoscale phenomena. The relationship between WWEs and the ENSO cycle is complex, involving among others the equatorial characteristics of the WWEs, the oceanic background state and the internal atmospheric variability. Both observational and modeling studies demonstrate that WWEs tend to cool the far western Pacific, shift the warm pool eastward and warm the central-eastern Pacific through the generation of Kelvin waves. They are therefore important processes for the central and eastern Pacific warming during the onset and development phase of El Niño. The strong atmospheric feedbacks that are likely to be generated by the ocean response to WWEs even suggest that a single WWE is capable of establishing the conditions under which El Niño can occur. The important role played by WWEs in the evolution and amplitude of recent El Niño events may therefore strongly limit the predictability of El Niño.

  1. High-fluoride groundwater.

    Science.gov (United States)

    Rao, N Subba

    2011-05-01

    Fluoride (F(-)) is essential for normal bone growth, but its higher concentration in the drinking water poses great health problems and fluorosis is common in many parts of India. The present paper deals with the aim of establishment of facts of the chemical characteristics responsible for the higher concentration of F(-) in the groundwater, after understanding the chemical behavior of F(-) in relation to pH, total alkalinity (TA), total hardness (TH), carbonate hardness (CH), non-carbonate hardness (NCH), and excess alkalinity (EA) in the groundwater observed from the known areas of endemic fluorosis zones of Andhra Pradesh that have abundant sources of F(-)-bearing minerals of the Precambrians. The chemical data of the groundwater shows that the pH increases with increase F(-); the concentration of TH is more than the concentration of TA at low F(-) groundwater, the resulting water is represented by NCH; the TH has less concentration compared to TA at high F(-) groundwater, causing the water that is characterized by EA; and the water of both low and high concentrations of F(-) has CH. As a result, the F(-) has a positive relation with pH and TA, and a negative relation with TH. The operating mechanism derived from these observations is that the F(-) is released from the source into the groundwater by geochemical reactions and that the groundwater in its flowpath is subjected to evapotranspiration due to the influence of dry climate, which accelerates a precipitation of CaCO(3) and a reduction of TH, and thereby a dissolution of F(-). Furthermore, the EA in the water activates the alkalinity in the areas of alkaline soils, leading to enrichment of F(-). Therefore, the alkaline condition, with high pH and EA, and low TH, is a more conducive environment for the higher concentration of F(-) in the groundwater.

  2. INDEPENDENT TECHNICAL REVIEW OF THE FOCUSED FEASIBILITY STUDY AND PROPOSED PLAN FOR DESIGNATED SOLID WASTE MANAGEMENT UNITS CONTRIBUTING TO THE SOUTHWEST GROUNDWATER PLUME AT THE PADUCAH GASEOUS DIFFUSION PLANT

    Energy Technology Data Exchange (ETDEWEB)

    Looney, B.; Eddy-Dilek, C.; Amidon, M.; Rossabi, J.; Stewart, L.

    2011-05-31

    The U. S. Department of Energy (DOE) is currently developing a Proposed Plan (PP) for remediation of designated sources of chlorinated solvents that contribute contamination to the Southwest (SW) Groundwater Plume at the Paducah Gaseous Diffusion Plant (PGDP), in Paducah, KY. The principal contaminants in the SW Plume are trichloroethene (TCE) and other volatile organic compounds (VOCs); these industrial solvents were used and disposed in various facilities and locations at PGDP. In the SW plume area, residual TCE sources are primarily in the fine-grained sediments of the Upper Continental Recharge System (UCRS), a partially saturated zone that delivers contaminants downward into the coarse-grained Regional Gravel Aquifer (RGA). The RGA serves as the significant lateral groundwater transport pathway for the plume. In the SW Plume area, the four main contributing TCE source units are: (1) Solid Waste Management Unit (SWMU) 1 / Oil Landfarm; (2) C-720 Building TCE Northeast Spill Site (SWMU 211A); (3) C-720 Building TCE Southeast Spill Site (SWMU 211B); and (4) C-747 Contaminated Burial Yard (SWMU 4). The PP presents the Preferred Alternatives for remediation of VOCs in the UCRS at the Oil Landfarm and the C-720 Building spill sites. The basis for the PP is documented in a Focused Feasibility Study (FFS) (DOE, 2011) and a Site Investigation Report (SI) (DOE, 2007). The SW plume is currently within the boundaries of PGDP (i.e., does not extend off-site). Nonetheless, reasonable mitigation of the multiple contaminant sources contributing to the SW plume is one of the necessary components identified in the PGDP End State Vision (DOE, 2005). Because of the importance of the proposed actions DOE assembled an Independent Technical Review (ITR) team to provide input and assistance in finalizing the PP.

  3. Trophic modeling of Eastern Boundary Current Systems: a review and prospectus for solving the “Peruvian Puzzle”

    Directory of Open Access Journals (Sweden)

    Marc H. Taylor

    2013-04-01

    Full Text Available Eastern Boundary Current systems (EBCSs are among the most productive fishing areas in the world. High primary and secondary productivity supports a large biomass of small planktivorous pelagic fish, “small pelagics”, which are important drivers of production to the entire system whereby they can influence both higher and lower trophic levels. Environmental variability causes changes in plankton (food quality and quantity, which can affect population sizes, distribution and domi-nance among small pelagics. This variability combined with impacts from the fishery complicate the development of management strategies. Consequently, much recent work has been in the development of multispecies trophic models to better understand interdependencies and system dynamics. Despite similarities in extent, structure and primary productivity between EBCSs, the Peruvian system greatly differs from the others in the magnitude of fish catches, due mainly to the incredible production of the anchovy Engraulis ringens. This paper reviews literature concerning EBCSs dynamics and the state-of-the-art in the trophic modeling of EBCSs. The objective is to critically analyze the potential of this approach for system understanding and management and to adapt existing steady-state models of the Peruvian system for use in (future dynamic simulations. A guideline for the construction of trophodynamic models is presented taking into account the important trophic and environmental interactions. In consideration of the importance of small pelagics for the system dynamics, emphasis is placed on developing appropriate model compartmentalization and spatial delineation that facilitates dynamic simulations. Methods of model validation to historical changes are presented to support hypotheses concerning EBCS dynamics and as a critical step to the development of predictive models. Finally, the identification of direct model links to easily obtainable abiotic parameters is

  4. Magnetic effects of hydrothermal alteration in porphyry copper and iron-oxide copper-gold systems: A review

    Science.gov (United States)

    Clark, David A.

    2014-06-01

    Magnetic anomaly patterns can be used as a tool for mapping lithology, metamorphic zones and hydrothermal alteration systems, as well as identifying structures that may control passage of magmas or hydrothermal fluids associated with mineralisation. Reliable geological interpretation of mineralised systems requires an understanding of the magmatic, metamorphic and hydrothermal processes that create, alter and destroy magnetic minerals in rocks. Predictive magnetic exploration models for porphyry copper and iron oxide copper-gold (IOCG) deposits can be derived from standard geological models by integrating magnetic petrological principles with petrophysical data, deposit descriptions, and modelling of observed magnetic signatures of these deposits. Even within a particular geological province, the magnetic signatures of similar deposits may differ substantially, due to differences in the local geological setting. Searching for “look-alike” signatures of a known deposit is likely to be unrewarding unless pertinent geological factors are taken into account. These factors include the tectonic setting and magma type, composition and disposition of host rocks, depth of emplacement and post-emplacement erosion level, depth of burial beneath younger cover, post-emplacement faulting and tilting, remanence effects contingent on ages of intrusion and alteration, and metamorphism. Because the effects of these factors on magnetic signatures are reasonably well understood, theoretical magnetic signatures appropriate for the local geological environment can qualitatively guide exploration and make semiquantitative predictions of anomaly amplitudes and patterns. The predictive models also allow detectability of deposit signatures to be assessed, for example when deposits are buried beneath a considerable thickness of nonmagnetic overburden, are covered by highly magnetic heterogeneous volcanic rocks, or there is a strong regional magnetic gradient. This paper reviews the

  5. Pain Assessment–Can it be Done with a Computerised System? A Systematic Review and Meta-Analysis

    Directory of Open Access Journals (Sweden)

    Nuno Pombo

    2016-04-01

    Full Text Available Background: Mobile and web technologies are becoming increasingly used to support the treatment of chronic pain conditions. However, the subjectivity of pain perception makes its management and evaluation very difficult. Pain treatment requires a multi-dimensional approach (e.g., sensory, affective, cognitive whence the evidence of technology effects across dimensions is lacking. This study aims to describe computerised monitoring systems and to suggest a methodology, based on statistical analysis, to evaluate their effects on pain assessment. Methods: We conducted a review of the English-language literature about computerised systems related to chronic pain complaints that included data collected via mobile devices or Internet, published since 2000 in three relevant bibliographical databases such as BioMed Central, PubMed Central and ScienceDirect. The extracted data include: objective and duration of the study, age and condition of the participants, and type of collected information (e.g., questionnaires, scales. Results: Sixty-two studies were included, encompassing 13,338 participants. A total of 50 (81% studies related to mobile systems, and 12 (19% related to web-based systems. Technology and pen-and-paper approaches presented equivalent outcomes related with pain intensity. Conclusions: The adoption of technology was revealed as accurate and feasible as pen-and-paper methods. The proposed assessment model based on data fusion combined with a qualitative assessment method was revealed to be suitable. Data integration raises several concerns and challenges to the design, development and application of monitoring systems applied to pain.

  6. The effects of global health initiatives on country health systems: a review of the evidence from HIV/AIDS control.

    Science.gov (United States)

    Biesma, Regien G; Brugha, Ruairí; Harmer, Andrew; Walsh, Aisling; Spicer, Neil; Walt, Gill

    2009-07-01

    This paper reviews country-level evidence about the impact of global health initiatives (GHIs), which have had profound effects on recipient country health systems in middle and low income countries. We have selected three initiatives that account for an estimated two-thirds of external funding earmarked for HIV/AIDS control in resource-poor countries: the Global Fund to Fight AIDS, TB and Malaria, the World Bank Multi-country AIDS Program (MAP) and the US President's Emergency Plan for AIDS Relief (PEPFAR). This paper draws on 31 original country-specific and cross-country articles and reports, based on country-level fieldwork conducted between 2002 and 2007. Positive effects have included a rapid scale-up in HIV/AIDS service delivery, greater stakeholder participation, and channelling of funds to non-governmental stakeholders, mainly NGOs and faith-based bodies. Negative effects include distortion of recipient countries' national policies, notably through distracting governments from coordinated efforts to strengthen health systems and re-verticalization of planning, management and monitoring and evaluation systems. Sub-national and district studies are needed to assess the degree to which GHIs are learning to align with and build the capacities of countries to respond to HIV/AIDS; whether marginalized populations access and benefit from GHI-funded programmes; and about the cost-effectiveness and long-term sustainability of the HIV and AIDS programmes funded by the GHIs. Three multi-country sets of evaluations, which will be reporting in 2009, will answer some of these questions.

  7. The long-term variability of Changma in the East Asian summer monsoon system: A review and revisit

    Science.gov (United States)

    Lee, June-Yi; Kwon, MinHo; Yun, Kyung-Sook; Min, Seung-Ki; Park, In-Hong; Ham, Yoo-Geun; Jin, Emilia Kyung; Kim, Joo-Hong; Seo, Kyong-Hwan; Kim, WonMoo; Yim, So-Young; Yoon, Jin-Ho

    2017-05-01

    Changma, which is a vital part of East Asian summer monsoon (EASM) system, plays a critical role in modulating water and energy cycles in Korea. Better understanding of its long-term variability and change is therefore a matter of scientific and societal importance. It has been indicated that characteristics of Changma have undergone significant interdecadal changes in association with the mid-1970s global-scale climate shift and the mid-1990s EASM shift. This paper reviews and revisits the characteristics on the long-term changes of Changma focusing on the underlying mechanisms for the changes. The four important features are manifested mainly during the last few decades: 1) mean and extreme rainfalls during Changma period from June to September have been increased with the amplification of diurnal cycle of rainfall, 2) the dry spell between the first and second rainy periods has become shorter, 3) the rainfall amount as well as the number of rainy days during August have significantly increased, probably due to the increase in typhoon landfalls, and 4) the relationship between the Changma rainfall and Western Pacific Subtropical High on interannual time scale has been enhanced. The typhoon contribution to the increase in heavy rainfall is attributable to enhanced interaction between typhoons and midlatitude baroclinic environment. It is noted that the change in the relationship between Changma and the tropical sea surface temperature (SST) over the Indian, Pacific, and Atlantic Oceans is a key factor in the long-term changes of Changma and EASM. Possible sources for the recent mid-1990s change include 1) the tropical dipole-like SST pattern between the central Pacific and Indo-Pacific region (the global warming hiatus pattern), 2) the recent intensification of tropical SST gradients among the Indian Ocean, the western Pacific, and the eastern Pacific, and 3) the tropical Atlantic SST warming.

  8. Microplastics in freshwater systems: a review of the emerging threats, identification of knowledge gaps and prioritisation of research needs.

    Science.gov (United States)

    Eerkes-Medrano, Dafne; Thompson, Richard C; Aldridge, David C

    2015-05-15

    Plastic contamination is an increasing environmental problem in marine systems where it has spread globally to even the most remote habitats. Plastic pieces in smaller size scales, microplastics (particles microplastic presence and interactions are equally as far reaching as are being observed in marine systems. Microplastics are being detected in freshwaters of Europe, North America, and Asia, and the first organismal studies are finding that freshwater fauna across a range of feeding guilds ingest microplastics. Drawing from the marine literature and these initial freshwater studies, we review the issue of microplastics in freshwater systems to summarise current understanding, identify knowledge gaps and suggest future research priorities. Evidence suggests that freshwater systems may share similarities to marine systems in the types of forces that transport microplastics (e.g. surface currents); the prevalence of microplastics (e.g. numerically abundant and ubiquitous); the approaches used for detection, identification and quantification (e.g. density separation, filtration, sieving and infrared spectroscopy); and the potential impacts (e.g. physical damage to organisms that ingest them, chemical transfer of toxicants). Differences between freshwater and marine systems include the closer proximity to point sources in freshwaters, the typically smaller sizes of freshwater systems, and spatial and temporal differences in the mixing/transport of particles by physical forces. These differences between marine and freshwater systems may lead to differences in the type of microplastics present. For example, rivers may show a predictable pattern in microplastic characteristics (size, shape, relative abundance) based on waste sources (e.g. household vs. industrial) adjacent to the river, and distance downstream from a point source. Given that the study of microplastics in freshwaters has only arisen in the last few years, we are still limited in our understanding of 1

  9. From forest to cropland and pasture systems: a critical review of soil organic carbon stocks changes in Amazonia.

    Science.gov (United States)

    Fujisaki, Kenji; Perrin, Anne-Sophie; Desjardins, Thierry; Bernoux, Martial; Balbino, Luiz Carlos; Brossard, Michel

    2015-02-26

    The impact of deforestation on soil organic carbon (SOC) stocks is important in the context of climate change and agricultural soil use. Trends of SOC stock changes after agroecosystem establishment vary according to the spatial scale considered, and factors explaining these trends may differ sometimes according to meta-analyses. We have reviewed the knowledge about changes in SOC stocks in Amazonia after the establishment of pasture or cropland, sought relationships between observed changes and soil, climatic variables and management practices, and synthesized the δ(13) C measured in pastures. Our dataset consisted of 21 studies mostly synchronic, across 52 sites (Brazil, Colombia, French Guiana, Suriname), totalling 70 forest-agroecosystem comparisons. We found that pastures (n = 52, mean age = 17.6 years) had slightly higher SOC stocks than forest (+6.8 ± 3.1 %), whereas croplands (n = 18, mean age = 8.7 years) had lower SOC stocks than forest (-8.5 ± 2.9 %). Annual precipitation and SOC stocks under forest had no effect on the SOC changes in the agroecosystems. For croplands, we found a lower SOC loss than other meta-analyses, but the short time period after deforestation here could have reduced this loss. There was no clear effect of tillage on the SOC response. Management of pastures, whether they were degraded/nominal/improved, had no significant effect on SOC response. δ(13) C measurements on 16 pasture chronosequences showed that decay of forest-derived SOC was variable, whereas pasture-derived SOC was less so and was characterized by an accumulation plateau of 20 Mg SOC ha(-1) after 20 years. The large uncertainties in SOC response observed could be derived from the chronosequence approach, sensitive to natural soil variability and to human management practices. This study emphasizes the need for diachronic and long-term studies, associated with better knowledge of agroecosystem management.

  10. Limits to global groundwater consumption

    Science.gov (United States)

    de Graaf, I.; Van Beek, L. P.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.

    2016-12-01

    Groundwater is the largest accessible freshwater resource worldwide and is of critical importance for irrigation, and so for global food security. For many regions of the world where groundwater abstraction exceeds groundwater recharge, persistent groundwater depletion occurs. A direct consequence of depletion is falling groundwater levels, reducing baseflows to rivers, harming ecosystems. Also, pumping costs increase, wells dry up and land subsidence can occur. Water demands are expected to increase further due to growing population, economic development and climate change, posing the urgent question how sustainable current water abstractions are worldwide and where and when these abstractions approach conceivable limits with all the associated problems. Here, we estimated past and future trends (1960-2050) in groundwater levels resulting from changes in abstractions and climate and predicted when limits of groundwater consumption are reached. We explored these limits by predicting where and when groundwater levels drop that low that groundwater becomes unattainable for abstractions and how river flows are affected. Water availabilities, abstractions, and lateral groundwater flows are simulated (5 arcmin. resolution) using a coupled version of the global hydrological model PCR-GLOBWB and a groundwater model based on MODFLOW. The groundwater model includes a parameterization of the worlds confined and unconfined aquifer systems, needed for a realistic simulation of groundwater head dynamics. Results show that, next to the existing regions experiencing groundwater depletion (like India, Pakistan, Central Valley) new regions will develop, e.g. Southern Europe, the Middle East, and Africa. Using a limit that reflects present-day feasibility of groundwater abstraction, we estimate that in 2050 groundwater becomes unattainable for 20% of the global population, mainly in the developing countries and pumping cost will increase significantly. Largest impacts are found

  11. Unsustainable Groundwater Exploitation and Stochastic Regime Shifts: Converging Management Constraints

    Science.gov (United States)

    Rao, Suresh; Park, Jeryang

    2014-05-01

    Increasing water security concerns arise from projected increases in competing freshwater demands, resulting from rapid urbanization, growing affluent population, and the need for increased production of food and bio-energy. These global trends in concert with the convergence of three groups of threats are likely to exacerbate freshwater security issues: (1) increasing dependency on effectively non-renewable groundwater ("peak water"); (2) increasing groundwater quality impairment("land-use intensification") from larger contaminant loads delivered from the vadose zone and surface water; and (3) increasing uncertainties in groundwater demand/supply from climate change ("stochastic risks"). Here, we present a conceptual framework for exploring water security threats, with a consideration of aquifers as complex hydrological systems with two stable states. Regime shifts in groundwater pumping -- from "sufficient" to "insufficient" -- result from changes in both internal system dynamics and external forcing from stochastic divers (non-stationary demands, hydro-climatic patterns). Examples from recent related work, in groundwater and surface water systems and ecosystems, are briefly reviewed as a prelude to presentation of model simulations of hypothetical scenarios of regime-shifts (tipping points) involving groundwater quantity and quality constraints. In addition to three types of widely recognized tipping points, we introduce a new type, stochastic tipping, that contributes to unexpected, undesirable regime shifts, resulting in inability to meet groundwater pumping needs, even when the perceived precariousness is small and the system is far from bifurcation point (deterministic tipping). Implications to sustainable groundwater management are discussed.

  12. Limits to Global Groundwater Consumption

    Science.gov (United States)

    Graaf, I. D.; Van Beek, R.; Sutanudjaja, E.; Wada, Y.; Bierkens, M. F.

    2015-12-01

    In regions with frequent water stress and large aquifer systems, groundwater is often used as an additional fresh water source. For many regions of the world groundwater abstraction exceeds groundwater recharge and persistent groundwater depletion occurs. The most direct effect of groundwater depletion is declining of water tables, leading to reduced groundwater discharge needed to sustain base-flow to e.g. rivers. Next to that, pumping costs increase, wells dry up and land subsidence occurs. These problems are expected to increase in the near future due to growing population and climate changes. This poses the urgent question of what the limits are of groundwater consumption worldwide. We simulate global water availability (5 arc-minute resolution, for 1960-2050) using the hydrological model PCR-GLOBWB (van Beek et al. 2011), coupled to a groundwater model based on MODFLOW (de Graaf et al. 2015), allowing for groundwater - surface water interactions. The groundwater model includes a parameterization of world's confined and unconfined aquifer systems needed for a realistic simulation of groundwater head dynamics. Water demands are included (from Wada et al. 2014). We study the limits to water consumption, focusing on locally attainable groundwater and groundwater levels critical to rivers to sustain low flows. We show an increasing trend (1960-2050) in groundwater head declines, due to increase in groundwater demand. Also, stream flow will decrease and low flow conditions will occur more frequent and will be longer in duration in the near future, especially for irrigated areas. Next to that, we provide a global overview of the years it takes until groundwater gets unattainable for e.g. a local farmer (100 m below land-surface used as a proxy), and estimate the increase in pumping cost for the near future. The results show where and when limits of groundwater consumption are reached globally.

  13. DS796 California Groundwater Units

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The California Groundwater Units dataset classifies and delineates the State into one of three groundwater based polygon units: (1) those areas defined as alluvial...

  14. Parameter Estimation and Experimental Design in Groundwater Modeling

    Institute of Scientific and Technical Information of China (English)

    SUN Ne-zheng

    2004-01-01

    This paper reviews the latest developments on parameter estimation and experimental design in the field of groundwater modeling. Special considerations are given when the structure of the identified parameter is complex and unknown. A new methodology for constructing useful groundwater models is described, which is based on the quantitative relationships among the complexity of model structure, the identifiability of parameter, the sufficiency of data, and the reliability of model application.

  15. Tehran Groundwater Chemical Pollution

    Directory of Open Access Journals (Sweden)

    M- Shariatpanahi

    1990-06-01

    Full Text Available Seventy eight wells water sample of Tehran plain were examined to determine r its groundwaters chemical pollution. Tehran s groundwaters are slightly acidic and their total dissolved solids are high and are in the hard water category."nThe nitrate concentration of wells water of west region is less than per¬missible level of W.H.O. standard, whereas, the nitrate concentration of some of the other regions wells exceed W.H.O. standard which is indication of pollution"nwith municipal wastewaters. The concentration of toxic elements Cr, Cd, As, Hg and"ni Pb of some of the west, east and south regions wells of Tehran is more than per¬missible level of W.H.O. standard, whereas, the concentration of Cu, Zn,Mn and detergents is below W.H.O. standard."n1"nIn general, the amount of dissolved materials of Tehran s groundwaters and also"ni the potential of their contamination with nitrate is increased as Tehran s ground-"nwaters move further to the south, and even though, Tehran s groundwaters contamination with toxic elements is limited to the industrial west district, industrial-residential east and south districts, but»with regard to the disposal methods of"nt municipal and industrial wastewaters, if Tehran s groundwaters pollution continues,"nlocal contamination of groundwaters is likely to spread. So that finally their quality changes in such a way that this water source may become unfit for most domestic, industrial and agricultural uses. This survey shows the necessity of collection and treatment of Tehran s wastewaters and Prevention of the disposal of untreated wastewaters into the environment.

  16. African financial systems: A review

    Directory of Open Access Journals (Sweden)

    Franklin Allen

    2011-04-01

    Full Text Available We start by providing an overview of financial systems in the African continent. We then consider the regions of Arab North Africa, West Africa, East and Central Africa, and Southern Africa in more detail. The paper covers, among other things, central banks, deposit-taking banks, non-bank institutions, such as the stock markets, fixed income markets, insurance markets, and microfinance institutions.

  17. In situ groundwater bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Hazen, Terry C.

    2009-02-01

    In situ groundwater bioremediation of hydrocarbons has been used for more than 40 years. Most strategies involve biostimulation; however, recently bioaugmentation have been used for dehalorespiration. Aquifer and contaminant profiles are critical to determining the feasibility and strategy for in situ groundwater bioremediation. Hydraulic conductivity and redox conditions, including concentrations of terminal electron acceptors are critical to determine the feasibility and strategy for potential bioremediation applications. Conceptual models followed by characterization and subsequent numerical models are critical for efficient and cost effective bioremediation. Critical research needs in this area include better modeling and integration of remediation strategies with natural attenuation.

  18. U/Th series radionuclides as coastal groundwater tracers

    Science.gov (United States)

    Swarzenski, P.W.

    2007-01-01

    times. The highly fractionated nature of U/Th series nuclides in groundwater is illustrated by the range in some measured activities. highest activities are typically observed for 222Rn, reflecting the inert nature of this noble gas. Groundwater 222Rn (t1/2=3.8) activities are thus controlled only by rapid in situ decay (Table 1) and production within host rocks, without the added complications of reversible removal via absorption or precipitation. Uranium, which is soluble as U(VI) in oxidizing waters, is present in intermediate activities in groundwaters that are moderated by redox-initiated removal onto aquifer rocks. The alkaline earth Ra and, to a greater extent, the less soluble actinide Th are readily removed from groundwater by water -- rock interactions and so are strongly depleted. Both of these elements have very short-lived as well as longer-lived isotopes, and so isotopes compositions reflect processes over a range of time scales. Many studies have evaluated and behavior of select radionuclides in groundwater and surface water systems. Recent advances in high-=precision mass spectrometry have opted new possibilities for more subtle interpretations in select long-lived U/Th series isotopes, such as U, Ra, Pa, and Th. However, these techniques have yet to be fully developed, ahns as a consequence, such data remain largely scarce and underutilized. Although many different approaches have been developed to study radionucluide behavior in groundwater, all are based on principles of radioactive production and decay and knowledge of source terms from weathering and recoil processes, as well as removal terms from the interaction with aquifer host rock surface by sorption and precipitation. This review is structured to present first a brief description of the background, driving forces, scales, and ecological significance of submarine groundwater discharge. Following this, a description of the geochemistry and behavior of select radionuclides in groundwater will be

  19. Groundwater: A Community Action Guide.

    Science.gov (United States)

    Boyd, Susan, Ed.; And Others

    Designed to be a guide for community action, this booklet examines issues and trends related to groundwater contamination. Basic concepts about groundwater and information about problems affecting it are covered under the categories of (1) what is groundwater? (2) availability and depletion; (3) quality and contamination; (4) public health…

  20. Groundwater: A Community Action Guide.

    Science.gov (United States)

    Boyd, Susan, Ed.; And Others

    Designed to be a guide for community action, this booklet examines issues and trends related to groundwater contamination. Basic concepts about groundwater and information about problems affecting it are covered under the categories of (1) what is groundwater? (2) availability and depletion; (3) quality and contamination; (4) public health…

  1. Regression modeling of ground-water flow

    Science.gov (United States)

    Cooley, R.L.; Naff, R.L.

    1985-01-01

    Nonlinear multiple regression methods are developed to model and analyze groundwater flow systems. Complete descriptions of regression methodology as applied to groundwater flow models allow scientists and engineers engaged in flow modeling to apply the methods to a wide range of problems. Organization of the text proceeds from an introduction that discusses the general topic of groundwater flow modeling, to a review of basic statistics necessary to properly apply regression techniques, and then to the main topic: exposition and use of linear and nonlinear regression to model groundwater flow. Statistical procedures are given to analyze and use the regression models. A number of exercises and answers are included to exercise the student on nearly all the methods that are presented for modeling and statistical analysis. Three computer programs implement the more complex methods. These three are a general two-dimensional, steady-state regression model for flow in an anisotropic, heterogeneous porous medium, a program to calculate a measure of model nonlinearity with respect to the regression parameters, and a program to analyze model errors in computed dependent variables such as hydraulic head. (USGS)

  2. PATHS groundwater hydrologic model

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, R.W.; Schur, J.A.

    1980-04-01

    A preliminary evaluation capability for two-dimensional groundwater pollution problems was developed as part of the Transport Modeling Task for the Waste Isolation Safety Assessment Program (WISAP). Our approach was to use the data limitations as a guide in setting the level of modeling detail. PATHS Groundwater Hydrologic Model is the first level (simplest) idealized hybrid analytical/numerical model for two-dimensional, saturated groundwater flow and single component transport; homogeneous geology. This document consists of the description of the PATHS groundwater hydrologic model. The preliminary evaluation capability prepared for WISAP, including the enhancements that were made because of the authors' experience using the earlier capability is described. Appendixes A through D supplement the report as follows: complete derivations of the background equations are provided in Appendix A. Appendix B is a comprehensive set of instructions for users of PATHS. It is written for users who have little or no experience with computers. Appendix C is for the programmer. It contains information on how input parameters are passed between programs in the system. It also contains program listings and test case listing. Appendix D is a definition of terms.

  3. GROUNDWATER RECHARGE AND CHEMICAL ...

    Science.gov (United States)

    The existing knowledge base regarding the presence and significance of chemicals foreign to the subsurface environment is large and growing -the papers in this volume serving as recent testament. But complex questions with few answers surround the unknowns regarding the potential for environmental or human health effects from trace levels of xenobiotics in groundwater, especially groundwater augmented with treated wastewater. Public acceptance for direct or indirect groundwater recharge using treated municipal wastewater ( especially sewage) spans the spectrum from unquestioned embrace to outright rejection. In this article, I detour around the issues most commonly discussed for groundwater recharge and instead focus on some of the less-recognized issues- those that emanate from the mysteries created at the many literal and virtual interfaces involved with the subsurface world. My major objective is to catalyze discussion that advances our understanding of the barriers to public acceptance of wastewater reuse -with its ultimate culmination in direct reuse for drinking. I pose what could be a key question as to whether much of the public's frustration or ambivalence in its decision making process for accepting or rejecting water reuse (for various purposes including personal use) emanates from fundamental inaccuracies, misrepresentation, or oversimplification of what water 'is' and how it functions in the environment -just what exactly is the 'water cyc

  4. Regulating groundwater use

    NARCIS (Netherlands)

    Hoogesteger van Dijk, Jaime; Wester, Flip

    2017-01-01

    Around the world it has proven very difficult to develop policies and interventions that ensure socio-environmentally sustainable groundwater use and exploitation. In the state of Guanajuato, Central Mexico, both the national government and the decentralized state government have pursued to regulate

  5. Reconciling Groundwater Storage Depletion Due to Pumping with Sustainability

    Directory of Open Access Journals (Sweden)

    Annukka Lipponen

    2010-11-01

    Full Text Available Groundwater pumping causes depletion of groundwater storage. The rate of depletion incurred by any new well is gradually decreasing and eventually becomes zero in the long run, after induced recharge and reduction of natural discharge of groundwater combined (capture have become large enough to balance the pumping rate completely. If aquifer-wide aggregated pumping rates are comparatively large, then such a new dynamic equilibrium may not be reached and groundwater storage may become exhausted. Decisions to pump groundwater are motivated by people’s need for domestic water and by expected benefits of using water for a variety of activities. But how much finally is abstracted from an aquifer (or is considered to be an optimal aggregate abstraction rate depends on a wide range of other factors as well. Among these, the constraint imposed by the groundwater balance (preventing aquifer exhaustion has received ample attention in the professional literature. However, other constraints or considerations related to changes in groundwater level due to pumping are observed as well and in many cases they even may dominate the decisions on pumping. This paper reviews such constraints or considerations, examines how they are or may be incorporated in the decision-making process, and evaluates to what extent the resulting pumping rates and patterns create conditions that comply with principles of sustainability.

  6. SSI's review of the Swedish Nuclear Fuel and Waste Management Co's (SKB) report on large-scale groundwater flow modelling for eastern Smaaland in Sweden (SKB Report 06-64); SSI:s granskning av SKB:s storregionala grundvattenmodellering foer oestra Smaaland (SKB Rapport 06-64)

    Energy Technology Data Exchange (ETDEWEB)

    Dverstorp, Bjorrn

    2007-09-15

    This report presents SSI's review of the Swedish Nuclear Fuel and Waste Management Co's (SKB) report (SKB Report 06-64) on large-scale groundwater flow modelling for eastern Smaaland in Sweden. SSI review is supported by two external review documents (included as appendices). SSI's review is part of a government decided consultation process on SKB's site investigations aimed at finding a suitable site for a spent nuclear fuel repository. SSI considers that SKB has presented a comprehensive study that contributes to the scientific understanding of how different factors influence the regional groundwater flow pattern. However, in SSI's opinion, SKB's evaluation of the modelling results is not complete enough to support SKB's conclusion that super regional flow conditions can be dismissed as a siting factor. SSI therefore recommends SKB to supplement their study in that respect and also to discuss the implications of identified differences in radionuclide travel times and migration distances on the overall assessment of the repository's longterm protective capability. SSI also recommends SKB to revisit some of their modelling assumptions to ensure that the model is set up in a way that does not block out large groundwater circulation cells. SSI's recommendations in this review should be regarded as guidance to SKB. SSI will make a formal assessment of how SKB has taken into account different siting factors, in connection with the review of SKB's license application to be submitted in 2009.

  7. Calibration of Models Using Groundwater Age (Invited)

    Science.gov (United States)

    Sanford, W. E.

    2009-12-01

    Water-resource managers are frequently concerned with the long-term ability of a groundwater system to deliver volumes of water for both humans and ecosystems under natural and anthropogenic stresses. Analysis of how a groundwater system responds to such stresses usually involves the construction and calibration of a numerical groundwater-flow model. The calibration procedure usually involves the use of both groundwater-level and flux observations. Water-level data are often more abundant, and thus the availability of flux data can be critical, with well discharge and base flow to streams being most often available. Lack of good flux data however is a common occurrence, especially in more arid climates where the sustainability of the water supply may be even more in question. Environmental tracers are frequently being used to estimate the “age” of a water sample, which represents the time the water has been in the subsurface since its arrival at the water table. Groundwater ages provide flux-related information and can be used successfully to help calibrate groundwater models if porosity is well constrained, especially when there is a paucity of other flux data. As several different methods of simulating groundwater age and tracer movement are possible, a review is presented here of the advantages, disadvantages, and potential pitfalls of the various numerical and tracer methods used in model calibration. The usefulness of groundwater ages for model calibration depends on the ability both to interpret a tracer so as to obtain an apparent observed age, and to use a numerical model to obtain an equivalent simulated age observation. Different levels of simplicity and assumptions accompany different methods for calculating the equivalent simulated age observation. The advantages of computational efficiency in certain methods can be offset by error associated with the underlying assumptions. Advective travel-time calculation using path-line tracking in finite

  8. Thermal use of groundwater: International legislation and ecological considerations

    Science.gov (United States)

    Hähnlein, S.; Griebler, C.; Blum, P.; Bayer, P.

    2009-04-01

    Groundwater fulfills various functions for nature, animals and humans. Certainly, groundwater has highest relevance as freshwater resource. Another increasingly important issue - especially considering rising oil and gas prices - is the use of aquifers as renewable energy reservoirs. In view of these two somehow conflictive uses it seems important to define legal regulations and management strategies where exploitation and protection of aquifers is balanced. Thermal use of groundwater with e.g. ground source heat pump (GSHP) systems results in temperature anomalies (cold or heat plumes) in the subsurface. The extension of these temperture plumes has to be known in order to interpret their influence on adjacent geothermal installations. Beside this technological constraint, there exists an ecological one: man made thermal anomalies may have undesirable effects on the groundwater ecosystem. To promote geothermal energy as an economically attractive, sustainable and environmentally friendly energy source, such constraints have to be integrated in regulations, planning and maintenance (Hähnlein et al. 2008a,b). The objective of this study is to review the current legal status of the thermal use of groundwater and to present first results how the ecosystem is influenced. • Legal viewpoint: The international legal situation on thermal groundwater use is very heterogeneous. Nationally and internationally there is no consistent legal situation. Minimum distances between GSHP and temperature limits for heating and cooling the groundwater vary strongly. Until now there are no scientifically based thresholds. And it is also legally unexplained which temperature changes are detrimental. This is due to the fact that there are no ecological and economical parameters established for sustainable groundwater use. • Ecological viewpoint: First results show that temperature changes that arise with the thermal use of groundwater can noticeably influence the composition of

  9. The Savannah River Site's Groundwater Monitoring Program

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-18

    This report summarizes the Savannah River Site (SRS) groundwater monitoring program conducted in the first quarter of 1990. It includes the analytical data, field data, well activity data, and the other documentation for this program and provides a record of the program's activities and rationale and an official document of the analytical results. The groundwater monitoring program includes the following activities: installation, maintenance, and abandonment of monitoring wells, environmental soil borings, development of the sampling and analytical schedule, collection and analyses of groundwater samples, review of the analytical data and other data, maintenance of the databases containing groundwater monitoring data and related data, quality assurance (QA) evaluations of laboratory performance, and reports of results to waste-site facility custodians and to the Environmental Protection Section (EPS) of EPD.

  10. The Savannah River Site's Groundwater Monitoring Program

    Energy Technology Data Exchange (ETDEWEB)

    1991-06-18

    This report summarizes the Savannah River Site (SRS) groundwater monitoring program conducted in the fourth quarter of 1990. It includes the analytical data, field data, well activity data, and other documentation for this program, provides a record of the program's activities and rationale, and serves as an official document of the analytical results. The groundwater monitoring program includes the following activities: installation, maintenance, and abandonment of monitoring wells, environmental soil borings, development of the sampling and analytical schedule, collection and analyses of groundwater samples, review of analytical and other data, maintenance of the databases containing groundwater monitoring data, quality assurance (QA) evaluations of laboratory performance, and reports of results to waste-site facility custodians and to the Environmental Protection Section (EPS) of EPD.

  11. Organic Carbon Fluxes in a Stressed Groundwater System

    Science.gov (United States)

    Baker, A.; Graham, P. W.; Grbich, N.; Chinu, K.; Yu, D.

    2013-12-01

    Dissolved Organic Carbon (DOC) flux in groundwater is poorly understood: influenced by recharge, extraction and surface processes. We reviewed existing datasets for DOC concentration and flux in Australian groundwater systems. In a temperate, semi-arid, Australian research site we measured variations in DOC content during a series of high intensity extraction and recovery events in the surrounding aquifer and abstracted groundwater. Groundwater was abstracted from a fractured basalt / metasediment aquifer overlain by residual soils and flanked by a Quaternary alluvial channel. Groundwater systems included the fractured rock system interconnected with the alluvial aquifer through a leaky aquitard and a perched aquifer held at the soil bedrock interface. Prior to and throughout the test, groundwater samples were collected from wells within the fractured rock, alluvial aquifer and soil bedrock interface and analysed for DOC. Initial DOC concentrations in the upper aquifer were ~2 mg/L, following pumping concentrations increased 36 mg/L (ave) peaking at 72 mg/L. In the lower aquifer initial TOC concentrations were ~1.6 mg/L, during pumping levels increased to 3.98 mg/L (ave) peaking at 14.32 mg/L. Results indicate the fractured rock aquifers ability to recharge was exceeded during intense pumping periods and a larger component of water was drawn from the upper aquifer. This increased the volume of water being drawn through the soil profile and increased DOC content in abstracted groundwater. Hydrological setting, well construction and pumping regime are likely to affect the concentration of DOC within abstracted groundwater. Further attention to abstracted groundwater as a component in terrestrial DOC fluxes is warranted.

  12. Groundwater hydrology instructional system

    Science.gov (United States)

    Schmidt, Ronald G.

    Wright State University, Dayton, Ohio, is preparing for its third cycle of the Interactive Remote Instructional System (IRIS) in groundwater hydrology, beginning January 15, 1986. The first cycle finished with an impressive completion ratio for registered participants, and the second cycle has currently been underway since July. This comprehensive hydrogeology program was originally developed for the Soil Conservation Service (of the U.S. Department of Agriculture) to prepare their personnel for professional practice work. Since its evolution into IRIS, an 80% participant completion rate has been recorded for the first cycle, which is a significant departure from success rates traditionally recorded by correspondence courses. This excellent rate of success is the result of 2 years of refinement and demonstrates the progressive nature of the program. IRIS has met the needs of participants by developing a curriculum that reflects current trends in the groundwater industry and has provided a unique educational approach that ensures maximum interaction between the instructional staff and participants.

  13. Contain contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Mutch, R.D. Jr.; Caputi, J.R. [Eckenfelder, Inc., Mahwah, NJ (United States); Ash, R.E. IV [Eckenfelder Inc., Nashville, TN (United States)

    1997-05-01

    Despite recent progress in innovative treatment technologies, many problems with contaminated groundwater still require the use of barrier walls, typically in combination with extraction and treatment systems. New technologies for subsurface barrier walls, mostly based on geomembranes, advancements in self-hardening slurries and permeation grouts with materials such as colloidal silica gel and montan wax emulsions, are being developed at an unprecedented pace. The paper discusses deep soil mixing, jet grouting, slurry trenches, and permeation grouting.

  14. Nitrate contamination of groundwater and its countermeasures

    Energy Technology Data Exchange (ETDEWEB)

    Mitamura, Hisayoshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    The inevitable increases of food production and energy consumption with an increase in world population become main causes of an increase of nitrate load to the environment. Although nitrogen is essential for the growth of animal and plant as a constituent element of protein, excessive nitrate load to the environment contaminates groundwater resources used as drinking water and leads to seriously adverse effects on the health of man and livestock. In order to clarify the problem of nitrate contamination of groundwater and search a new trend of technology development from the viewpoint of environment remediation and protection, the present paper has reviewed adverse effects of nitrate on human health, the actual state of nitrogen cycle, several kinds of nitrate sources, measures for reducing nitrate level, etc. (author)

  15. GROUNDWATER PROTECTION MANAGEMENT PROGRAM DESCRIPTION.

    Energy Technology Data Exchange (ETDEWEB)

    PAQUETTE,D.E.; BENNETT,D.B.; DORSCH,W.R.; GOODE,G.A.; LEE,R.J.; KLAUS,K.; HOWE,R.F.; GEIGER,K.

    2002-05-31

    THE DEPARTMENT OF ENERGY ORDER 5400.1, GENERAL ENVIRONMENTAL PROTECTION PROGRAM, REQUIRES THE DEVELOPMENT AND IMPLEMENTATION OF A GROUNDWATER PROTECTION PROGRAM. THE BNL GROUNDWATER PROTECTION MANAGEMENT PROGRAM DESCRIPTION PROVIDES AN OVERVIEW OF HOW THE LABORATORY ENSURES THAT PLANS FOR GROUNDWATER PROTECTION, MONITORING, AND RESTORATION ARE FULLY DEFINED, INTEGRATED, AND MANAGED IN A COST EFFECTIVE MANNER THAT IS CONSISTENT WITH FEDERAL, STATE, AND LOCAL REGULATIONS.

  16. Groundwater types in Southeast Srem

    Directory of Open Access Journals (Sweden)

    Gregorić Enike

    2009-01-01

    Full Text Available The region of Southeast Srem is rich in ground waters, which is of great significance to agricultural production. The objective of this paper was to designate the zones of different groundwater types from the aspect of recharge, based on the analysis of groundwater regimes in the study area. A very complex groundwater regime in Southeast Srem, which depends on a great number of natural and some anthropogenic factors, makes it difficult to designate clearly the zones of the three main types of groundwater regime. Still, the boundaries of the zones of groundwater regime types were defined based on the results of correlation analysis of the basic factors affecting the groundwater regime. Zone I includes the climatic type of groundwater. Its fluctuation corresponds to the vertical factors of water balance (precipitation and evaporation and it is not affected by the river water level. This zone extends North and East of the line Putinci, Golubinci, Stara Pazova, Batajnica, Dobanovci, mainly in the area of the loess plateau. Within the zone, groundwater is at a relatively great depth. Only exceptionally, in the valleys, it appears almost on the surface. Zone II includes the climatic-hydrological groundwater type, which is the transition between the climatic type and the hydrological type. The fluctuation of groundwater regime is affected both by the effect of vertical balance factors, and by the effect of watercourses. Climatic-hydrological groundwater type covers the central and the lowest part of the study area and the South part of the middle terrace. Zone III is classified as the hydrological groundwater type and it covers the riparian areas along the Sava and the Danube. The aquifer is hydraulically connected with the river Sava.

  17. SPECIFIC SOLUTIONS GROUNDWATER FLOW EQUATION

    OpenAIRE

    Syahruddin, Muhammad Hamzah

    2014-01-01

    Geophysic publication Groundwater flow under surface, its usually slow moving, so that in laminer flow condition can find analisys using the Darcy???s law. The combination between Darcy law and continuity equation can find differential Laplace equation as general equation groundwater flow in sub surface. Based on Differential Laplace Equation is the equation that can be used to describe hydraulic head and velocity flow distribution in porous media as groundwater. In the modeling Laplace e...

  18. The groundwater subsidy to vegetation: groundwater exchanges between landcover patches

    Science.gov (United States)

    Steven, L. I.; Gimenez, R.; Jobbagy, E. G.

    2015-12-01

    The Gran Chaco is a hot, dry plain, that spans over 60 million hectares across Bolivia, Paraguay, Brazil and Argentina. It supports high biodiversity in its dry forest and savannahs, but is rapidly being converted to agriculture in response to growing soy demand and technology including genetic modification and zero-till, that has made cultivation in drier landscapes more viable. Under natural conditions, the deep-rooted, native vegetation of the Chaco effectively captured all rainfall for evapotranspiration resulting in near zero groundwater recharge under the dry forest. Conversion to shallower rooted soy and corn, combined with the fallow period prior to the growing season, reduces evapotranspiration and allows some water to percolate through the root zone and recharge the groundwater system. When this groundwater recharge occurs, it creates groundwater mounding and a hydraulic gradient that drives flow to adjacent landcover patches where recharge does not occur. As the watertable rises, groundwater becomes available to the deep-rooted, dry forest vegetation. We develop a soil and groundwater flow model to simulate infiltration, percolation, evaporation, rootwater uptake, groundwater recharge and the lateral transfer of water between adjacent landcover patches to quantify this groundwater subsidy from converted agricultural lands to remnant patches of dry forest.

  19. Intensive groundwater use: a silent revolution that cannot be ignored.

    Science.gov (United States)

    Llamas, M R; Martínez-Santos, P

    2005-01-01

    Over the last decades, agriculture in arid and semi-arid countries has experienced a true "silent revolution" of intensive groundwater use. Millions of independent farmers worldwide have chosen to become increasingly dependent on the reliability of groundwater resources, and as a result their countries have reaped abundant social and economic benefits. Data from several countries shows that groundwater irrigation presents a much greater efficiency, than surface water irrigation systems, thus contributing to fulfil the motto of "more crops and jobs per drop". If this situation is confirmed globally, the usual world water visions have to be reviewed. However, the "silent revolution" has been carried out with scarce control on the part of governmental water agencies, and thus a series of unwanted effects have developed in certain places. While these by no means justify the pervasive "hydromyths" and obsolete paradigms that voice the frailty of groundwater, appropriate management of groundwater resources remains a worldwide challenge. This paper provides an overview of these issues, and concludes with the necessity there is to educate all levels of society on the importance of groundwater and to create bottom-up user associations to manage aquifers as common pool resources.

  20. Reviews

    Science.gov (United States)

    2004-03-01

    WEB WATCH (204) Try unearthing some interesting information about archaeology BOOK REVIEWS (206) Teaching and assessing practical skills Book Review: Learn to drive with Sir Isaac Newton DVD REVIEW (207) Bring some sunshine into the classroom EQUIPMENT REVIEWS (208) Robust air puck takes a kicking Flowlog offers sensing options plus multimode datalogging Mastering Chladni figures takes practice but it offers surprises

  1. Solutions Remediate Contaminated Groundwater

    Science.gov (United States)

    2010-01-01

    During the Apollo Program, NASA workers used chlorinated solvents to clean rocket engine components at launch sites. These solvents, known as dense non-aqueous phase liquids, had contaminated launch facilities to the point of near-irreparability. Dr. Jacqueline Quinn and Dr. Kathleen Brooks Loftin of Kennedy Space Center partnered with researchers from the University of Central Florida's chemistry and engineering programs to develop technology capable of remediating the area without great cost or further environmental damage. They called the new invention Emulsified Zero-Valent Iron (EZVI). The groundwater remediation compound is cleaning up polluted areas all around the world and is, to date, NASA's most licensed technology.

  2. Tracer attenuation in groundwater

    Science.gov (United States)

    Cvetkovic, Vladimir

    2011-12-01

    The self-purifying capacity of aquifers strongly depends on the attenuation of waterborne contaminants, i.e., irreversible loss of contaminant mass on a given scale as a result of coupled transport and transformation processes. A general formulation of tracer attenuation in groundwater is presented. Basic sensitivities of attenuation to macrodispersion and retention are illustrated for a few typical retention mechanisms. Tracer recovery is suggested as an experimental proxy for attenuation. Unique experimental data of tracer recovery in crystalline rock compare favorably with the theoretical model that is based on diffusion-controlled retention. Non-Fickian hydrodynamic transport has potentially a large impact on field-scale attenuation of dissolved contaminants.

  3. Groundwater remediation optimization using artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, L. L., LLNL

    1998-05-01

    One continuing point of research in optimizing groundwater quality management is reduction of computational burden which is particularly limiting in field-scale applications. Often evaluation of a single pumping strategy, i.e. one call to the groundwater flow and transport model (GFTM) may take several hours on a reasonably fast workstation. For computational flexibility and efficiency, optimal groundwater remediation design at Lawrence Livermore National Laboratory (LLNL) has relied on artificial neural networks (ANNS) trained to approximate the outcome of 2-D field-scale, finite difference/finite element GFTMs. The search itself has been directed primarily by the genetic algorithm (GA) or the simulated annealing (SA) algorithm. This approach has advantages of (1) up to a million fold increase in speed of remediation pattern assessment during the searches and sensitivity analyses for the 2-D LLNL work, (2) freedom from sequential runs of the GFTM (enables workstation farming), and (3) recycling of the knowledge base (i.e. runs of the GFTM necessary to train the ANNS). Reviewed here are the background and motivation for such work, recent applications, and continuing issues of research.

  4. Classification of groundwater at the Nevada Test Site

    Energy Technology Data Exchange (ETDEWEB)

    Chapman, J.B.

    1994-08-01

    Groundwater occurring at the Nevada Test Site (NTS) has been classified according to the ``Guidelines for Ground-Water Classification Under the US Environmental Protection Agency (EPA) Ground-Water Protection Strategy`` (June 1988). All of the groundwater units at the NTS are Class II, groundwater currently (IIA) or potentially (IIB) a source of drinking water. The Classification Review Area (CRA) for the NTS is defined as the standard two-mile distance from the facility boundary recommended by EPA. The possibility of expanding the CRA was evaluated, but the two-mile distance encompasses the area expected to be impacted by contaminant transport during a 10-year period (EPA,s suggested limit), should a release occur. The CRA is very large as a consequence of the large size of the NTS and the decision to classify the entire site, not individual areas of activity. Because most activities are located many miles hydraulically upgradient of the NTS boundary, the CRA generally provides much more than the usual two-mile buffer required by EPA. The CRA is considered sufficiently large to allow confident determination of the use and value of groundwater and identification of potentially affected users. The size and complex hydrogeology of the NTS are inconsistent with the EPA guideline assumption of a high degree of hydrologic interconnection throughout the review area. To more realistically depict the site hydrogeology, the CRA is subdivided into eight groundwater units. Two main aquifer systems are recognized: the lower carbonate aquifer system and the Cenozoic aquifer system (consisting of aquifers in Quaternary valley fill and Tertiary volcanics). These aquifer systems are further divided geographically based on the location of low permeability boundaries.

  5. Sustainable groundwater management in California

    Science.gov (United States)

    Phillips, Steven P.; Rogers, Laurel Lynn; Faunt, Claudia

    2015-12-01

    The U.S. Geological Survey (USGS) uses data collection, modeling tools, and scientific analysis to help water managers plan for, and assess, hydrologic issues that can cause “undesirable results” associated with groundwater use. This information helps managers understand trends and investigate and predict effects of different groundwater-management strategies.

  6. Promoting local management in groundwater

    Science.gov (United States)

    van Steenbergen, Frank

    2006-03-01

    There is a strong case for making greater effort to promote local groundwater management—in addition to other measures that regulate groundwater use. Though scattered, there are several examples—from India, Pakistan, Yemen and Egypt—where groundwater users effectively self-imposed restrictions on the use of groundwater. There are a number of recurrent themes in such spontaneously-developed examples of local regulation: the importance of not excluding potential users; the importance of simple, low transaction cost rules; the power of correct and accessible hydrogeological information; the possibility of making more use of demand and supply management strategies; and the important supportive role of local governments. The case is made, using examples, for actively promoting local groundwater management as an important element in balancing groundwater uses. Two programmes for promoting local groundwater management in South India are described—one focussing on participatory hydrological monitoring, and one focussing on micro-resource planning and training. In both cases the response was very positive and the conclusion is that promoting local groundwater regulation is not difficult, costly or sensitive and can reach the necessary scale quickly.

  7. Decadal variations in groundwater quality

    DEFF Research Database (Denmark)

    Jessen, Søren; Postma, Dieke; Thorling, Lærke

    2017-01-01

    Twenty-five years of groundwater quality monitoring in a sandy aquifer beneath agricultural fields showed large temporal and spatial variations in major ion groundwater chemistry, which were linked closely to the nitrate (NO3) content of agricultural recharge. Between 1988 and 2013, the NO3 content...... loading. Agriculture thus is an important determinant of major ion groundwater chemistry. Temporal and spatial variations in the groundwater quality were simulated using a 2D reactive transport model, which combined effects of the historical NO3 leaching and denitrification, with dispersive mixing...... into the pristine groundwater residing deeper in the aquifer. Reactant-to-product ratios across reaction fronts are altered by dispersive mixing and transience in reactant input functions. Modelling therefore allowed a direct comparison of observed and simulated ratios of concentrations of NO3 (reactant...

  8. The Savannah River Site Groundwater Monitoring Program Fourth Quarter 2000 (October thru December 2000)

    Energy Technology Data Exchange (ETDEWEB)

    Dukes, M.D.

    2001-08-02

    This report summarizes the Groundwater Monitoring Program conducted by SRS during fourth quarter 2000. It includes the analytical data, field data, data review, quality control, and other documentation for this program.

  9. Artificial recharge of groundwater

    Science.gov (United States)

    The Task Committee on Guidelines for Artificial Recharge of Groundwater, of the American Society of Civil Engineers' (ASCE) Irrigation and Drainage Division, sponsored an International Symposium on Artificial Recharge of Groundwater at the Inn-at-the-Park Hotel in Anaheim, Calif., August 23-27, 1988. Cosponsors were the U.S. Geological Survey, California Department of Water Resources, University of California Water Resources Center, Metropolitan Water District of Southern California, with cooperation from the U.S. Bureau of Reclamation, International Association of Hydrological Sciences, American Water Resources Association, U.S. Agency for International Development, World Bank, United Nations Department of Technical Cooperation for Development, and a number of local and state organizations.Because of the worldwide interest in artificial recharge and the need to develop efficient recharge facilities, the Anaheim symposium brought together an interdisciplinary group of engineers and scientists to provide a forum for many professional disciplines to exchange experiences and findings related to various types of artificial recharge; learn from both successful and unsuccessful case histories; promote technology transfer between the various disciplines; provide an education resource for communication with those who are not water scientists, such as planners, lawyers, regulators, and the public in general; and indicate directions by which cities or other entities can save funds by having reasonable technical guidelines for implementation of a recharge project.

  10. The Savannah River Site's Groundwater Monitoring Program

    Energy Technology Data Exchange (ETDEWEB)

    1992-08-03

    This report summarizes the Savannah River Site (SRS) groundwater monitoring program conducted during the first quarter of 1992. It includes the analytical data, field data, data review, quality control, and other documentation for this program; provides a record of the program's activities; and serves as an official document of the analytical results.

  11. The Savannah River Site's groundwater monitoring program

    Energy Technology Data Exchange (ETDEWEB)

    1991-10-18

    This report summarizes the Savannah River Site (SRS) groundwater monitoring program conducted by EPD/EMS in the first quarter of 1991. In includes the analytical data, field data, data review, quality control, and other documentation for this program, provides a record of the program's activities and rationale, and serves as an official document of the analytical results.

  12. Hydrological drought. Processes and estimation methods for streamflow and groundwater

    NARCIS (Netherlands)

    Tallaksen, L.; Lanen, van H.A.J.

    2004-01-01

    Hydrological drought is a textbook for university students, practising hydrologists and researchers. The main scope of this book is to provide the reader with a comprehensive review of processes and estimation methods for streamflow and groundwater drought. It includes a qualitative conceptual

  13. Recent developments in modeling groundwater systems

    Energy Technology Data Exchange (ETDEWEB)

    Narasimhan, T.N.; Witherspoon, P.A.

    1977-05-20

    This paper reviews the developments in the mathematical modeling of groundwater systems over the past decde. The first part of the paper is devoted to a description of the physics of the different types of problems that are of interest in hydrogeology and a statement of the related initial-boundary-value problems. The various numerical techniques that have been employed to solve the governing equations are discussed in the second part. In the third section a few typical case histories are presented to illustrate the trend of progress that has occurred in the application of mathematical modeling to actual field problems.

  14. Analytical and numerical study of the thermal feedback in Groundwater Heat Pumps (GWHP)

    Science.gov (United States)

    Casasso, Alessandro; Sethi, Rajandrea

    2014-05-01

    .J., Tsang C.F., 1980, Ground-water use for cooling: associated aquifer temperature changes, Ground Water 18, pp. 452-458 Luo J., Kitanidis P.K., 2004, Fluid residence times within a recirculation zone created by an extraction-injection well pair, Journal of Hydrology 295, pp. 149-162 Milnes E., Perrochet P., 2013, Assessing the impact of thermal feedback and recycling in open-loop groundwater heat pump (GWHP) systems: a complementary design tool, Hydrogeology Journal 21, pp. 505-514 Strack O.D.L., 1988, Groundwater Mechanics, Prentice-Hall, Englewood Cliffs, NJ (USA)

  15. Reconstruction of groundwater depletion using a global scale groundwater model

    Science.gov (United States)

    de Graaf, Inge; van Beek, Rens; Sutanudjaja, Edwin; Wada, Yoshi; Bierkens, Marc

    2015-04-01

    Groundwater forms an integral part of the global hydrological cycle and is the world's largest accessible source of fresh water to satisfy human water needs. It buffers variable recharge rates over time, thereby effectively sustaining river flows in times of drought as well as evaporation in areas with shallow water tables. Moreover, although lateral groundwater flows are often slow, they cross topographic and administrative boundaries at appreciable rates. Despite the importance of groundwater, most global scale hydrological models do not consider surface water-groundwater interactions or include a lateral groundwater flow component. The main reason of this omission is the lack of consistent global-scale hydrogeological information needed to arrive at a more realistic representation of the groundwater system, i.e. including information on aquifer depths and the presence of confining layers. The latter holds vital information on the accessibility and quality of the global groundwater resource. In this study we developed a high resolution (5 arc-minutes) global scale transient groundwater model comprising confined and unconfined aquifers. This model is based on MODFLOW (McDonald and Harbaugh, 1988) and coupled with the land-surface model PCR GLOBWB (van Beek et al., 2011) via recharge and surface water levels. Aquifers properties were based on newly derived estimates of aquifer depths (de Graaf et al., 2014b) and thickness of confining layers from an integration of lithological and topographical information. They were further parameterized using available global datasets on lithology (Hartmann and Moosdorf, 2011) and permeability (Gleeson et al., 2014). In a sensitivity analysis the model was run with various hydrogeological parameter settings, under natural recharge only. Scenarios of past groundwater abstractions and corresponding recharge (Wada et al., 2012, de Graaf et al. 2014a) were evaluated. The resulting estimates of groundwater depletion are lower than

  16. [Quantitative method of representative contaminants in groundwater pollution risk assessment].

    Science.gov (United States)

    Wang, Jun-Jie; He, Jiang-Tao; Lu, Yan; Liu, Li-Ya; Zhang, Xiao-Liang

    2012-03-01

    In the light of the problem that stress vulnerability assessment in groundwater pollution risk assessment is lack of an effective quantitative system, a new system was proposed based on representative contaminants and corresponding emission quantities through the analysis of groundwater pollution sources. And quantitative method of the representative contaminants in this system was established by analyzing the three properties of representative contaminants and determining the research emphasis using analytic hierarchy process. The method had been applied to the assessment of Beijing groundwater pollution risk. The results demonstrated that the representative contaminants hazards greatly depended on different research emphasizes. There were also differences between the sequence of three representative contaminants hazards and their corresponding properties. It suggested that subjective tendency of the research emphasis had a decisive impact on calculation results. In addition, by the means of sequence to normalize the three properties and to unify the quantified properties results would zoom in or out of the relative properties characteristic of different representative contaminants.

  17. Application of optimisation techniques in groundwater quantity and quality management

    Indian Academy of Sciences (India)

    Amlan Das; Bithin Datta

    2001-08-01

    This paper presents the state-of-the-art on application of optimisation techniques in groundwater quality and quantity management. In order to solve optimisation-based groundwater management models, researchers have used various mathematical programming techniques such as linear programming (LP), nonlinear programming (NLP), mixed-integer programming (MIP), optimal control theory-based mathematical programming, differential dynamic programming (DDP), stochastic programming (SP), combinatorial optimisation (CO), and multiple objective programming for multipurpose management. Studies reported in the literature on the application of these methods are reviewed in this paper.

  18. Bioremediation of contaminated groundwater

    Science.gov (United States)

    Hazen, Terry C.; Fliermans, Carl B.

    1995-01-01

    An apparatus and method for in situ remediation of contaminated subsurface soil or groundwater contaminated by chlorinated hydrocarbons. A nutrient fluid is selected to stimulate the growth and reproduction of indigenous subsurface microorganisms that are capable of degrading the contaminants; an oxygenated fluid is selected to create a generally aerobic environment for these microorganisms to degrade the contaminants, leaving only pockets that are anaerobic. The nutrient fluid is injected periodically while the oxygenated fluid is injected continuously and both are extracted so that both are drawn across the plume. The nutrient fluid stimulates microbial colony growth; withholding it periodicially forces the larger, healthy colony of microbes to degrade the contaminants. Treatment is continued until the subsurface concentration of contaminants is reduced to an acceptable, preselected level. The nutrient fluid can be methane and the oxygenated fluid air for stimulating production of methanotrophs to break down chlorohydrocarbons, especially trichloroethylene (TCE) and tetrachloroethylene.

  19. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2012-01-01

    Groundwater is a vital resource and also a dynamic component of the water cycle. Unconfined aquifer storage is less responsive to short term weather conditions than the near surface terrestrial water storage (TWS) components (soil moisture, surface water, and snow). However, save for the permanently frozen regions, it typically exhibits a larger range of variability over multi-annual periods than the other components. Groundwater is poorly monitored at the global scale, but terrestrial water storage (TWS) change data from the Gravity Recovery and Climate Experiment (GRACE) satellite mission are a reasonable proxy for unconfined groundwater at climatic scales.

  20. Fresh Groundwater Resources in Georgia and Management Problems

    Science.gov (United States)

    Gaprindashvili, George; Gaprindashvili, Merab

    2015-04-01

    Fresh water represents conditioned factor for human body's life. That's why the superiority of drinking water is recognized as human body's priority according to the international declarations. World is experiencing deficit of quality water. Natural Disasters caused by the pollution of the fresh groundwater is also very painful and acute, because it needed more time, more material and financial means for the liquidation of their results, and what the most important practically is, it is impossible to renew the initial natural conditions completely. All these conditions that the rational use of fresh groundwater passed by the interests of separate countries and became worldwide, international problem - fresh water became as considerable raw material for the worlds import and export. The fresh groundwater place the important role among the water recourses of Georgia. Their existing is considerably connected to the development of industry and agriculture, also with water supply issue of populated area. Groundwater management requires precise knowledge of sources (aquifers). Monitoring of Georgia's most important aquifers started many years ago and has provided large amount of data. This was interrupted at the beginning of the 1990s. It could be noted that fresh water existing in the country is distinguished with high quality. According to the mineralization and temperature parameters groundwater is generally divided into the following groups: 1) Fresh drinking waters (mineralization not exceeding 1.0 g/l); 2) Mineral waters (mineralization over 1.0 g/l); 3) Thermal waters -- healing (20˚C - 35˚C), Geothermal (40˚C - 108˚C). Below we present briefly review about the situation of fresh groundwater resources, started recovery of groundwater monitoring network and the analysis of the management problems.

  1. Impact of runoff infiltration on contaminant accumulation and transport in the soil/filter media of Sustainable Urban Drainage Systems: A literature review.

    Science.gov (United States)

    Tedoldi, Damien; Chebbo, Ghassan; Pierlot, Daniel; Kovacs, Yves; Gromaire, Marie-Christine

    2016-11-01

    The increasing use of Sustainable Urban Drainage Systems (SUDS) for stormwater management raises some concerns about the fate of ubiquitous runoff micropollutants in soils and their potential threat to groundwater. This question may be addressed either experimentally, by sampling and analyzing SUDS soil after a given operating time, or with a modeling approach to simulate the fate and transport of contaminants. After briefly reminding the processes responsible for the retention, degradation, or leaching of several urban-sourced contaminants in soils, this paper presents the state of the art about both experimental and modeling assessments. In spite of noteworthy differences in the sampling protocols, the soil parameters chosen as explanatory variables, and the methods used to evaluate the site-specific initial concentrations, most investigations undoubtedly evidenced a significant accumulation of metals and/or hydrocarbons in SUDS soils, which in the majority of the cases appears to be restricted to the upper 10 to 30cm. These results may suggest that SUDS exhibit an interesting potential for pollution control, but antinomic observations have also been made in several specific cases, and the inter-site concentration variability is still difficult to appraise. There seems to be no consensus regarding the level of complexity to be used in models. However, the available data deriving from experimental studies is generally limited to the contamination profiles and a few parameters of the soil, as a result of which "complex" models (including colloid-facilitated transport for example) appear to be difficult to validate before using them for predictive evaluations.

  2. GROUNDWATER HYDROCHEMISTRY EVALUATION IN RURAL ...

    African Journals Online (AJOL)

    Osondu

    2012-10-09

    Oct 9, 2012 ... the quality of groundwater from domestic water supply boreholes across rural Botswana. Ionic ... quality limits the supply of potable fresh water. To utilize and protect valuable water ..... prescribed specification of World Health.

  3. Groundwater Vulnerability Regions of Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — The regions onThis map represent areas with similar hydrogeologic characteristics thought to represent similar potentials for contamination of groundwater and/or...

  4. Ensemble models on palaeoclimate to predict India's groundwater challenge

    Directory of Open Access Journals (Sweden)

    Partha Sarathi Datta

    2013-09-01

    Full Text Available In many parts of the world, freshwater crisis is largely due to increasing water consumption and pollution by rapidly growing population and aspirations for economic development, but, ascribed usually to the climate. However, limited understanding and knowledge gaps in the factors controlling climate and uncertainties in the climate models are unable to assess the probable impacts on water availability in tropical regions. In this context, review of ensemble models on δ18O and δD in rainfall and groundwater, 3H- and 14C- ages of groundwater and 14C- age of lakes sediments helped to reconstruct palaeoclimate and long-term recharge in the North-west India; and predict future groundwater challenge. The annual mean temperature trend indicates both warming/cooling in different parts of India in the past and during 1901–2010. Neither the GCMs (Global Climate Models nor the observational record indicates any significant change/increase in temperature and rainfall over the last century, and climate change during the last 1200 yrs BP. In much of the North-West region, deep groundwater renewal occurred from past humid climate, and shallow groundwater renewal from limited modern recharge over the past decades. To make water management to be more responsive to climate change, the gaps in the science of climate change need to be bridged.

  5. Quality assessment of groundwater from the south-eastern Arabian Peninsula.

    Science.gov (United States)

    Zhang, H W; Sun, Y Q; Li, Y; Zhou, X D; Tang, X Z; Yi, P; Murad, A; Hussein, S; Alshamsi, D; Aldahan, A; Yu, Z B; Chen, X G; Mugwaneza, V D P

    2017-08-01

    Assessment of groundwater quality plays a significant role in the utilization of the scarce water resources globally and especially in arid regions. The increasing abstraction together with man-made contamination and seawater intrusion have strongly affected groundwater quality in the Arabia Peninsula, exemplified by the investigation given here from the United Arab Emirates, where the groundwater is seldom reviewed and assessed. In the aim of assessing current groundwater quality, we here present a comparison of chemical data linked to aquifers types. The results reveal that most of the investigated groundwater is not suitable for drinking, household, and agricultural purposes following the WHO permissible limits. Aquifer composition and climate have vital control on the water quality, with the carbonate aquifers contain the least potable water compared to the ophiolites and Quaternary clastics. Seawater intrusion along coastal regions has deteriorated the water quality and the phenomenon may become more intensive with future warming climate and rising sea level.

  6. Assessment of the development of aquifer management councils (COTAS) for sustainable groundwater management in Guanajuato, Mexico

    Science.gov (United States)

    Wester, Philippus; Sandoval Minero, Ricardo; Hoogesteger, Jaime

    2011-06-01

    Collective groundwater management by water users—self-regulation—is increasingly advocated as a complement to state regulation. This article analyzes the attempts by the Guanajuato State Water Commission (CEAG) in central Mexico to promote user self-regulation through the establishment and development of 14 Consejos Técnicos de Aguas (COTAS; Technical Water Councils). Based on a joint assessment by a former senior CEAG policy-maker and two researchers, Guanajuato's groundwater-management policy is reviewed to understand why user self-regulation was less successful than expected. It concludes that increasing awareness and improving the knowledge base on groundwater is not enough to trigger self-regulation by groundwater users. A wider delegation of responsibilities to the COTAS is necessary, combined with: (1) functioning mechanisms for enforcing groundwater legislation, especially concerning well permits and pumped volumes, and (2) mechanisms that ensure the legitimacy and accountability of users' representatives to both users and state agencies.

  7. Groundwater Monitoring Plan for the Reactor Technology Complex Operable Unit 2-13

    Energy Technology Data Exchange (ETDEWEB)

    Richard P. Wells

    2007-03-23

    This Groundwater Monitoring Plan describes the objectives, activities, and assessments that will be performed to support the on-going groundwater monitoring requirements at the Reactor Technology Complex, formerly the Test Reactor Area (TRA). The requirements for groundwater monitoring were stipulated in the Final Record of Decision for Test Reactor Area, Operable Unit 2-13, signed in December 1997. The monitoring requirements were modified by the First Five-Year Review Report for the Test Reactor Area, Operable Unit 2-13, at the Idaho National Engineering and Environmental Laboratory to focus on those contaminants of concern that warrant continued surveillance, including chromium, tritium, strontium-90, and cobalt-60. Based upon recommendations provided in the Annual Groundwater Monitoring Status Report for 2006, the groundwater monitoring frequency was reduced to annually from twice a year.

  8. What is the impact on fish recruitment of anthropogenic physical and structural habitat change in shallow nearshore areas in temperate systems? A systematic review protocol

    DEFF Research Database (Denmark)

    MacUra, B.; Lönnstedt, O.M.; Byström, P.

    2016-01-01

    and spawning habitats of many fish and other aquatic species. Several coastal fish populations have seen marked declines in abundance and diversity during the past two decades. A systematic review on the topic would clarify if anthropogenic physical and structural changes of near-shore areas have effects...... on fish recruitment and which these effects are. Methods: The review will examine how various physical and structural anthropogenic changes of nearshore fish habitats affect fish recruitment. Relevant studies include small- and large-scale field studies in marine and brackish systems or large lakes...

  9. Quality-assurance plan for groundwater activities, U.S. Geological Survey, Washington Water Science Center

    Science.gov (United States)

    Kozar, Mark D.; Kahle, Sue C.

    2013-01-01

    This report documents the standard procedures, policies, and field methods used by the U.S. Geological Survey’s (USGS) Washington Water Science Center staff for activities related to the collection, processing, analysis, storage, and publication of groundwater data. This groundwater quality-assurance plan changes through time to accommodate new methods and requirements developed by the Washington Water Science Center and the USGS Office of Groundwater. The plan is based largely on requirements and guidelines provided by the USGS Office of Groundwater, or the USGS Water Mission Area. Regular updates to this plan represent an integral part of the quality-assurance process. Because numerous policy memoranda have been issued by the Office of Groundwater since the previous groundwater quality assurance plan was written, this report is a substantial revision of the previous report, supplants it, and contains significant additional policies not covered in the previous report. This updated plan includes information related to the organization and responsibilities of USGS Washington Water Science Center staff, training, safety, project proposal development, project review procedures, data collection activities, data processing activities, report review procedures, and archiving of field data and interpretative information pertaining to groundwater flow models, borehole aquifer tests, and aquifer tests. Important updates from the previous groundwater quality assurance plan include: (1) procedures for documenting and archiving of groundwater flow models; (2) revisions to procedures and policies for the creation of sites in the Groundwater Site Inventory database; (3) adoption of new water-level forms to be used within the USGS Washington Water Science Center; (4) procedures for future creation of borehole geophysics, surface geophysics, and aquifer-test archives; and (5) use of the USGS Multi Optional Network Key Entry System software for entry of routine water-level data

  10. Reviews.

    Science.gov (United States)

    Greenleaf, Floyd; And Others

    1986-01-01

    Reviews eight textbooks, readers, and books. Topics include Latin America, colonial America, the Carolinians, women in French textbooks, the Vikings, the Soviet Union, nineteenth-century Black America, and Ernest Rutherford. (TRS)

  11. Reviews.

    Science.gov (United States)

    Science Teacher, 1987

    1987-01-01

    Provides reviews of four computer software packages designed for use in science education. Describes courseware dealing with a variety of tips for teaching physics concepts, chemical reactions in an aqueous solution, mitosis and meiosis, and photosynthesis. (TW)

  12. Review

    African Journals Online (AJOL)

    2016-01-01

    Jan 1, 2016 ... medicine and biology here an attempt has been made to review the synthesis and biological ... insight into the recent applications of Mannich reaction and its ...... Various thermodynamic parameters were also determined to ...

  13. Reviews

    Directory of Open Access Journals (Sweden)

    1990-06-01

    Full Text Available Michael Issacharoff. Discourse as Performance . Stanford: Stanford University Press, 1989. vii + 161 pp. Reviewed by Gerald Prince, University of Pennsylvania Thomas M. Kavanagh, ed. The Limits of Theory . Stanford: Stanford University Press, 1989. 254 pp. Reviewed by André J.M. Prévos, Pennsylvania State University, Worthington Scranton Campus Wendy B. Faris. Labyrinths of Language: Symbolic Landscape and Narrative Design in Modern Fiction . Baltimore and London: The Johns Hopkins Press, 1988. 242 pp. Reviewed by Carol Rigolot, Princeton University Eve Tavor Bannet. Structuralism and the Logic of Dissent: Barthes, Derrida, Foucault, Lacan . Urbana and Chicago: University of Illinois Press, 1989. 299 pp. Reviewed by Andrew J. McKenna, Loyoyla University of Chicago Gary Saul Morson and Caryl Emerson, eds. Rethinking Bakhtin: Extensions and Challenges . Evanston: Northwestern University Press, 1989. Reviewed by Lewis Bagby, University of Wyoming Fernando Moreno. Carlos Fuentes. La mort d'Artemio Cruz: entre le mythe et l'histoire . Paris: Editions Caribeennes, 1989. Reviewed by Susan Levine, Lawrence, Kansas

  14. A review and evaluation of the Langley Research Center's Scientific and Technical Information Program. Results of phase 5. Design and evaluation of STI systems: A selected, annotated bibliography

    Science.gov (United States)

    Pinelli, T. E.; Hinnebusch, P. A.; Jaffe, J. M.

    1981-01-01

    A selected, annotated bibliography of literature citations related to the design and evaluation of STI systems is presented. The use of manual and machine-readable literature searches; the review of numerous books, periodicals reports, and papers; and the selection and annotation of literature citations were required. The bibliography was produced because the information was needed to develop the methodology for the review and evaluation project, and a survey of the literature did not reveal the existence of a single published source of information pertinent to the subject. Approximately 200 citations are classified in four subject areas. The areas include information - general; information systems - design and evaluation, including information products and services; information - use and need; and information - economics.

  15. Application of Moving Bed Biofilm Reactor (MBBR) and Integrated Fixed Activated Sludge (IFAS) for Biological River Water Purification System: A Short Review

    Science.gov (United States)

    Lariyah, M. S.; Mohiyaden, H. A.; Hayder, G.; Hayder, G.; Hussein, A.; Basri, H.; Sabri, A. F.; Noh, MN

    2016-03-01

    This review paper present the MBBR and IFAS technology for urban river water purification including both conventional methods and new emerging technologies. The aim of this paper is to present the MBBR and IFAS technology as an alternative and successful method for treating different kinds of effluents under different condition. There are still current treatment technologies being researched and the outcomes maybe available in a while. The review also includes many relevant researches carried out at the laboratory and pilot scales. This review covers the important processes on MBBR and IFAS basic treatment process, affecting of carrier type and influent types. However, the research concluded so far are compiled herein and reported for the first time to acquire a better perspective and insight on the subject with a view of meeting the news approach. The research concluded so far are compiled herein and reported for the first time to acquire a better perspective and insight on the subject with a view of meeting the news approach. To this end, the most feasible technology could be the combination of advanced biological process (bioreactor systems) including MBBR and IFAS system.

  16. The Adverse Effects of Heavy Metals with and without Noise Exposure on the Human Peripheral and Central Auditory System: A Literature Review

    Directory of Open Access Journals (Sweden)

    Marie-Josée Castellanos

    2016-12-01

    Full Text Available Exposure to some chemicals in the workplace can lead to occupational chemical-induced hearing loss. Attention has mainly focused on the adverse auditory effects of solvents. However, other chemicals such as heavy metals have been also identified as ototoxic agents. The aim of this work was to review the current scientific knowledge about the adverse auditory effects of heavy metal exposure with and without co-exposure to noise in humans. PubMed and Medline were accessed to find suitable articles. A total of 49 articles met the inclusion criteria. Results from the review showed that no evidence about the ototoxic effects in humans of manganese is available. Contradictory results have been found for arsenic, lead and mercury as well as for the possible interaction between heavy metals and noise. All studies found in this review have found that exposure to cadmium and mixtures of heavy metals induce auditory dysfunction. Most of the studies investigating the adverse auditory effects of heavy metals in humans have investigated human populations exposed to lead. Some of these studies suggest peripheral and central auditory dysfunction induced by lead exposure. It is concluded that further evidence from human studies about the adverse auditory effects of heavy metal exposure is still required. Despite this issue, audiologists and other hearing health care professionals should be aware of the possible auditory effects of heavy metals.

  17. Analytical Methods for the Determination of the Distribution of Total Petroleum Hydrocarbons in the Water and Sediment of Aquatic Systems: A Review

    Directory of Open Access Journals (Sweden)

    A. O. Adeniji

    2017-01-01

    Full Text Available Several methods of extraction and analytical determination for total petroleum hydrocarbons (TPHCs in aqueous and solid samples are reviewed. Infrared spectroscopy is one of the efficient methods that are being replaced today pursuant to getting rid of some halogenated solvents classified as ozone-depleting substances. The gravimetric method which uses n-hexane as an extraction solvent for the determination of oil and grease, as well as the nonpolar materials, has become a preferred choice, despite being not suitable for volatiles because of the mandatory evaporation step. Other frequently used methods include gas chromatography with a flame ionization detector (FID or mass spectrometric detector (MSD which has the capacity to reveal the type of hydrocarbons present and is applicable to both volatile and semivolatile samples. Ultraviolet fluorescence is another method that is available both as a portable field device and as off-site laboratory equipment. Each of the methods has its own advantages and disadvantages; hence, the choice of method is guided by the type of data needed as discussed in detail in this review. The distribution of TPHC in water and sediments across the globe and the factors influencing the distribution were also reviewed.

  18. The Adverse Effects of Heavy Metals with and without Noise Exposure on the Human Peripheral and Central Auditory System: A Literature Review.

    Science.gov (United States)

    Castellanos, Marie-Josée; Fuente, Adrian

    2016-12-09

    Exposure to some chemicals in the workplace can lead to occupational chemical-induced hearing loss. Attention has mainly focused on the adverse auditory effects of solvents. However, other chemicals such as heavy metals have been also identified as ototoxic agents. The aim of this work was to review the current scientific knowledge about the adverse auditory effects of heavy metal exposure with and without co-exposure to noise in humans. PubMed and Medline were accessed to find suitable articles. A total of 49 articles met the inclusion criteria. Results from the review showed that no evidence about the ototoxic effects in humans of manganese is available. Contradictory results have been found for arsenic, lead and mercury as well as for the possible interaction between heavy metals and noise. All studies found in this review have found that exposure to cadmium and mixtures of heavy metals induce auditory dysfunction. Most of the studies investigating the adverse auditory effects of heavy metals in humans have investigated human populations exposed to lead. Some of these studies suggest peripheral and central auditory dysfunction induced by lead exposure. It is concluded that further evidence from human studies about the adverse auditory effects of heavy metal exposure is still required. Despite this issue, audiologists and other hearing health care professionals should be aware of the possible auditory effects of heavy metals.

  19. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2011-01-01

    Most people think of groundwater as a resource, but it is also a useful indicator of climate variability and human impacts on the environment. Groundwater storage varies slowly relative to other non-frozen components of the water cycle, encapsulating long period variations and trends in surface meteorology. On seasonal to interannual timescales, groundwater is as dynamic as soil moisture, and it has been shown that groundwater storage changes have contributed to sea level variations. Groundwater monitoring well measurements are too sporadic and poorly assembled outside of the United States and a few other nations to permit direct global assessment of groundwater variability. However, observational estimates of terrestrial water storage (TWS) variations from the GRACE satellites largely represent groundwater storage variations on an interannual basis, save for high latitude/altitude (dominated by snow and ice) and wet tropical (surface water) regions. A figure maps changes in mean annual TWS from 2009 to 2010, based on GRACE, reflecting hydroclimatic conditions in 2010. Severe droughts impacted Russia and the Amazon, and drier than normal weather also affected the Indochinese peninsula, parts of central and southern Africa, and western Australia. Groundwater depletion continued in northern India, while heavy rains in California helped to replenish aquifers that have been depleted by drought and withdrawals for irrigation, though they are still below normal levels. Droughts in northern Argentina and western China similarly abated. Wet weather raised aquifer levels broadly across western Europe. Rains in eastern Australia caused flooding to the north and helped to mitigate a decade long drought in the south. Significant reductions in TWS seen in the coast of Alaska and the Patagonian Andes represent ongoing glacier melt, not groundwater depletion. Figures plot time series of zonal mean and global GRACE derived non-seasonal TWS anomalies (deviation from the mean of

  20. Progress, opportunities, and key fields for groundwater quality research under the impacts of human activities in China with a special focus on western China.

    Science.gov (United States)

    Li, Peiyue; Tian, Rui; Xue, Chenyang; Wu, Jianhua

    2017-05-01

    Groundwater quality research is extremely important for supporting the safety of the water supply and human health in arid and semi-arid areas of China. This review article was constructed to report the latest research progress of groundwater quality in western China where groundwater quality is undergoing fast deterioration because of fast economic development and extensive anthropogenic activities. The opportunities brought by increasing public awareness of groundwater quality protection were also highlighted and discussed. To guide and promote further development of groundwater quality research in China, especially in western China, ten key groundwater quality research fields were proposed. The review shows that the intensification of human activities and the associated impacts on groundwater quality in China, especially in western China, has made groundwater quality research increasingly important, and has caught the attention of local, national, and international agencies and scholars. China has achieved some progress in groundwater quality research in terms of national and regional laws, regulations, and financial supports. The future of groundwater quality research in China, especially in western China, is promising reflected by the opportunities highlighted. The key research fields proposed in this article may also inform groundwater quality protection and management at the national and international level.

  1. Groundwater recharge and agricultural contamination

    Science.gov (United States)

    Böhlke, J.K.

    2002-01-01

    Agriculture has had direct and indirect effects on the rates and compositions of groundwater recharge and aquifer biogeochemistry. Direct effects include dissolution and transport of excess quantities of fertilizers and associated materials and hydrologic alterations related to irrigation and drainage. Some indirect effects include changes in water-rock reactions in soils and aquifers caused by increased concentrations of dissolved oxidants, protons, and major ions. Agrilcultural activities have directly or indirectly affected the concentrations of a large number of inorganic chemicals in groundwater, for example NO3-, N2, Cl, SO42-, H+, P, C, K, Mg, Ca, Sr, Ba, Ra, and As, as well a wide variety of pesticides and other organic compounds. For reactive contaminants like NO3-, a combination of chemical, isotopic, and environmental-tracer analytical approaches might be required to resolve changing inputs from subsequent alterations as causes of concentration gradients in groundwater. Groundwater records derived from multi-component hydrostratigraphic data can be used to quantify recharge rates and residence times of water and dissolved contaminants, document past variations in recharging contaminant loads, and identify natural contaminant-remediation processes. These data indicate that many of the world's surficial aquifers contain transient records of changing agricultural contamination from the last half of the 20th century. The transient agricultural groundwater signal has important implications for long-term trends and spatial heterogeneity in discharge.

  2. Index-based groundwater vulnerability mapping models using hydrogeological settings: A critical evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Prashant, E-mail: prashantkumar@csio.res.in [CSIR-Central Scientific Instruments Organisation, Chandigarh 160030 (India); Academy of Scientific and Innovative Research—CSIO, Chandigarh 160030 (India); Bansod, Baban K.S.; Debnath, Sanjit K. [CSIR-Central Scientific Instruments Organisation, Chandigarh 160030 (India); Academy of Scientific and Innovative Research—CSIO, Chandigarh 160030 (India); Thakur, Praveen Kumar [Indian Institute of Remote Sensing (ISRO), Dehradun 248001 (India); Ghanshyam, C. [CSIR-Central Scientific Instruments Organisation, Chandigarh 160030 (India); Academy of Scientific and Innovative Research—CSIO, Chandigarh 160030 (India)

    2015-02-15

    Groundwater vulnerability maps are useful for decision making in land use planning and water resource management. This paper reviews the various groundwater vulnerability assessment models developed across the world. Each model has been evaluated in terms of its pros and cons and the environmental conditions of its application. The paper further discusses the validation techniques used for the generated vulnerability maps by various models. Implicit challenges associated with the development of the groundwater vulnerability assessment models have also been identified with scientific considerations to the parameter relations and their selections. - Highlights: • Various index-based groundwater vulnerability assessment models have been discussed. • A comparative analysis of the models and its applicability in different hydrogeological settings has been discussed. • Research problems of underlying vulnerability assessment models are also reported in this review paper.

  3. Impact of climate change on irrigation requirements in terms of groundwater resources

    OpenAIRE

    Zhou, Yu; Zwahlen, François; Wang, Yanxin; Li, Yilian

    2013-01-01

    Climate change affects not only water resources but also water demand for irrigation. A large proportion of the world’s agriculture depends on groundwater, especially in arid and semi-arid regions. In several regions, aquifer resources face depletion. Groundwater recharge has been viewed as a by-product of irrigation return flow, and with climate change, aquifer storage of such flow will be vital. A general review, for a broad-based audience, is given of work on global warming and groundwater...

  4. Modeling Groundwater Depletion at Regional and Global Scales: Present State and Future Prospects

    Science.gov (United States)

    Wada, Yoshihide

    2016-03-01

    Except for frozen water in ice and glaciers, groundwater is the world's largest distributed store of freshwater and has strategic importance to global food and water security. In this paper, the most recent advances quantifying groundwater depletion (GWD) are comprehensively reviewed. This paper critically evaluates the recently advanced modeling approaches estimating GWD at regional and global scales, and the evidence of feedbacks to the Earth system including sea-level rise associated with GWD. Finally, critical challenges and opportunities in the use of groundwater are identified for the adaption to growing food demand and uncertain climate.

  5. Modelling Groundwater Depletion at Regional and Global Scales: Present State and Future Prospects.

    Science.gov (United States)

    Wada, Yoshihide

    2015-01-01

    Except for frozen water in ice and glaciers, groundwater is the world's largest distributed store of freshwater and has strategic importance to global food and water security. In this paper, the most recent advances quantifying groundwater depletion (GWD) are comprehensively reviewed. This paper critically evaluates the recently advanced modeling approaches estimating GWD at regional and global scales, and the evidence of feedbacks to the Earth system including sea-level rise associated with GWD. Finally, critical challenges and opportunities in the use of groundwater are identified for the adaption to growing food demand and uncertain climate.

  6. Vulnerability Assessment of Groundwater Resources by Nutrient Source Apportionment to Individual Groundwater Wells: A Case Study in North Carolina

    Science.gov (United States)

    Ayub, R.; Obenour, D. R.; Keyworth, A. J.; Genereux, D. P.; Mahinthakumar, K.

    2016-12-01

    Groundwater contamination by nutrients (nitrogen and phosphorus) is a major concern in water table aquifers that underlie agricultural areas in the mid-Atlantic Coastal Plain of the United States. High nutrient concentrations leaching into shallow groundwater can lead to human health problems and eutrophication of receiving surface waters. Liquid manure from concentrated animal feeding operations (CAFOs) stored in open-air lagoons and applied to spray fields can be a significant source of nutrients to groundwater, along with septic waste. In this study, we developed a model-based methodology for source apportionment and vulnerability assessment using sparse groundwater quality sampling measurements for Duplin County, North Carolina (NC), obtained by the NC Department of Environmental Quality (NC DEQ). This model provides information relevant to management by estimating the nutrient transport through the aquifer from different sources and addressing the uncertainty of nutrient contaminant propagation. First, the zones of influence (dependent on nutrient pathways) for individual groundwater monitoring wells were identified using a two-dimensional vertically averaged groundwater flow and transport model incorporating geologic uncertainty for the surficial aquifer system. A multiple linear regression approach is then applied to estimate the contribution weights for different nutrient source types using the nutrient measurements from monitoring wells and the potential sources within each zone of influence. Using the source contribution weights and their uncertainty, a probabilistic vulnerability assessment of the study area due to nutrient contamination is performed. Knowledge of the contribution of different nutrient sources to contamination at receptor locations (e.g., private wells, municipal wells, stream beds etc.) will be helpful in planning and implementation of appropriate mitigation measures.

  7. Uranium in groundwater — Fertilizers versus geogenic sources

    Energy Technology Data Exchange (ETDEWEB)

    Liesch, Tanja, E-mail: tanja.liesch@kit.edu; Hinrichsen, Sören; Goldscheider, Nico

    2015-12-01

    Due to its radiological and toxicological properties even at low concentration levels, uranium is increasingly recognized as relevant contaminant in drinking water from aquifers. Uranium originates from different sources, including natural or geogenic, mining and industrial activities, and fertilizers in agriculture. The goal of this study was to obtain insights into the origin of uranium in groundwater while differentiating between geogenic sources and fertilizers. A literature review concerning the sources and geochemical processes affecting the occurrence and distribution of uranium in the lithosphere, pedosphere and hydrosphere provided the background for the evaluation of data on uranium in groundwater at regional scale. The state of Baden-Württemberg, Germany, was selected for this study, because of its hydrogeological and land-use diversity, and for reasons of data availability. Uranium and other parameters from N = 1935 groundwater monitoring sites were analyzed statistically and geospatially. Results show that (i) 1.6% of all water samples exceed the German legal limit for drinking water (10 μg/L); (ii) The range and spatial distribution of uranium and occasional peak values seem to be related to geogenic sources; (iii) There is a clear relation between agricultural land-use and low-level uranium concentrations, indicating that fertilizers generate a measurable but low background of uranium in groundwater. - Highlights: • Uranium concentrations in groundwater in Southwest Germany mainly depend on geology. • Only 1.6% of 1935 samples exceed the German legal limit for drinking water of 10 μg/L. • The percentage of positive uranium detections (> 0.5 μg/L) is higher in agricultural areas. • Phosphate fertilizers cause significant increase of uranium in groundwater at low concentration levels.

  8. What is the existing evidence supporting the efficacy of compression bandage systems containing both elastic and inelastic components (mixed-component systems)? A systematic review.

    Science.gov (United States)

    Welsh, Lynn

    2017-05-01

    To analyse current evidence on the efficacy of bandage systems containing both elastic and inelastic components (mixed-component systems). International consensus on the efficacy of types of compression systems is difficult to achieve; however, mixed-component systems are being promoted as combining the best properties of both elastic and inelastic bandage systems and increasingly being used to treat venous leg ulcers in practice. A systematic literature review. Search terms such as venous leg ulcer, varicose ulcer, leg ulcer, compression, bandage, elastic, inelastic, short stretch, healing rate, interface pressure, mixed component, two-layer, four-layer and multi-layer were used in database and hand searches in several combinations. Limits were set for years 2005-March 2015 and English-language publications. A total of 475 studies were identified at initial search, and following elimination from abstract and title, this was reduced to 7. A further study was identified on Google Scholar, bringing the final number of studies fitting inclusion criteria to 8. The following subgroups relating to outcomes of efficacy were identified: ulcer healing, maintenance of interface pressure, slippage, ease of application and patient quality of life. Mixed-component systems were found to have comparable ulcer healing rates to alternative compression systems and be easy to apply; have similar abilities to maintain pressure as four-layer bandages and better abilities than short-stretch bandages; have less slippage than alternative systems; and to be significantly associated with several favourable quality of life outcomes. Clinician skill in bandage application was an uncontrolled variable in all eight papers included in the review, which may limit reliability of findings. This review synthesises existing evidence on the efficacy of mixed-component systems and encourages clinicians to regard them as an effective alternative to purely elastic or inelastic compression systems

  9. Reviews

    OpenAIRE

    Revista alicantina de estudios ingleses

    1995-01-01

    Contiene: M. Carmen África Vidal Claramonte. Traducción, manipulación, desconstrucción. Colección Biblioteca Filológica de Salamanca. Salamanca: Ediciones Colegio de España, 1995 / reviewed by Enrique Alcaraz Varó; Diccionario de uso inglés-español/Spanish-English. Directed by Aquilino Sánchez. Madrid: SGEL, 1993, 450 pp. Diccionario de uso pocket inglés-español/Spanish- English. Directed by Aquilino Sánchez. Madrid: SGEL, 1993, 274 pages / reviewed by Miguel Ángel Campos Pardillo...

  10. Groundwater resource-directed measures software

    African Journals Online (AJOL)

    2006-07-21

    Jul 21, 2006 ... 1Institute for Groundwater Studies, University of the Free State, PO Box 339, Bloemfontein, 9300, South Africa ... In this paper the methods developed for the GRDM .... The geothermal gradient for groundwater, that is, the.

  11. ASSESSMENT OF GROUNDWATER QUALITY IN SHALLOW ...

    African Journals Online (AJOL)

    development of human societies. In Okrika Island ... abstraction of groundwater due to population increase in Port ... 298. Nwankwoala and Walter: Assessment of Groundwater Quality in Shallow Coastal Aquifers ..... and Tai-Eleme areas.

  12. Future research needs involving pathogens in groundwater

    Science.gov (United States)

    Contamination of groundwater by enteric pathogens has commonly been associated with disease outbreaks. Proper management and treatment of pathogen sources are important barriers to preventing groundwater contamination. However, non-point sources of pathogen contamination are frequently difficult to ...

  13. Valuing groundwater: A practical approach for integrating ...

    African Journals Online (AJOL)

    groundwater economic values into decision making ... The methodology incorporates a 2-tiered valuation approach. .... groundwater systems in Botswana (SADC, 2010). .... tion) can be investigated to support water resource management.

  14. INTEC Groundwater Monitoring Report 2006

    Energy Technology Data Exchange (ETDEWEB)

    J. R. Forbes

    2007-02-01

    This report summarizes 2006 perched water and groundwater monitoring activities at the Idaho Nuclear Technology and Engineering Center (INTEC) located at the Idaho National Laboratory (INL). During 2006, groundwater samples were collected from a total of 22 Snake River Plain Aquifer (SRPA) monitoring wells, plus six aquifer wells sampled for the Idaho CERCLA Disposal Facility (ICDF) monitoring program. In addition, perched water samples were collected from 21 perched wells and 19 suction lysimeters. Groundwater and perched water samples were analyzed for a suite of radionuclides and inorganic constituents. Laboratory results in this report are compared to drinking water maximum contaminant levels (MCLs). Such comparison is for reference only and it should be noted that the Operable Unit 3-13 Record of Decision does not require that perched water comply with drinking water standards.

  15. Groundwater arsenic contamination throughout China.

    Science.gov (United States)

    Rodríguez-Lado, Luis; Sun, Guifan; Berg, Michael; Zhang, Qiang; Xue, Hanbin; Zheng, Quanmei; Johnson, C Annette

    2013-08-23

    Arsenic-contaminated groundwater used for drinking in China is a health threat that was first recognized in the 1960s. However, because of the sheer size of the country, millions of groundwater wells remain to be tested in order to determine the magnitude of the problem. We developed a statistical risk model that classifies safe and unsafe areas with respect to geogenic arsenic contamination in China, using the threshold of 10 micrograms per liter, the World Health Organization guideline and current Chinese standard for drinking water. We estimate that 19.6 million people are at risk of being affected by the consumption of arsenic-contaminated groundwater. Although the results must be confirmed with additional field measurements, our risk model identifies numerous arsenic-affected areas and highlights the potential magnitude of this health threat in China.

  16. Identification and Selection of Alternative Scenarios in LCA Studies of Integrated Waste Management Systems: A Review of Main Issues and Perspectives

    Directory of Open Access Journals (Sweden)

    Andrea Raggi

    2012-09-01

    Full Text Available Life Cycle Assessment (LCA is a decision support tool that can be used to assess the environmental performance of an integrated waste management system or to identify the system with the best performance through a comparative analysis of different scenarios. The results of the analysis depend primarily on how the scenarios to be compared are defined, that is on which waste fractions are assumed to be sent to certain treatments/destinations and in what amounts. This paper reviews LCAs of integrated waste management systems with the aim of exploring how the scenarios to be compared are defined in the preliminary phase of an LCA. This critical review highlighted that various criteria, more or less subjective, are generally used for the definition of scenarios. Furthermore, the number of scenarios identified and compared is generally limited; this may entail that only the best option among a limited set of possibilities can be selected, instead of identifying the best of all possible combinations. As a result, the advisability of identifying an integrated life cycle-based methodological approach that allows finding the most environmentally sound scenario among all of those that are theoretically possible is stressed.

  17. Food supply reliance on groundwater

    Science.gov (United States)

    Dalin, Carole; Puma, Michael; Wada, Yoshihide; Kastner, Thomas

    2016-04-01

    Water resources, essential to sustain human life, livelihoods and ecosystems, are under increasing pressure from population growth, socio-economic development and global climate change. As the largest freshwater resource on Earth, groundwater is key for human development and food security. Yet, excessive abstraction of groundwater for irrigation, driven by an increasing demand for food in recent decades, is leading to fast exhaustion of groundwater reserves in major agricultural areas of the world. Some of the highest depletion rates are observed in Pakistan, India, California Central Valley and the North China Plain aquifers. In addition, the growing economy and population of several countries, such as India and China, makes prospects of future available water and food worrisome. In this context, it is becoming particularly challenging to sustainably feed the world population, without exhausting our water resources. Besides, food production and consumption across the globe have become increasingly interconnected, with many areas' agricultural production destined to remote consumers. In this globalisation era, trade is crucial to the world's food system. As a transfer of water-intensive goods, across regions with varying levels of water productivity, food trade can save significant volumes of water resources globally. This situation makes it essential to address the issue of groundwater overuse for global food supply, accounting for international food trade. To do so, we quantify the current, global use of non-renewable groundwater for major crops, accounting for various water productivity and trade flows. This will highlight areas requiring quickest attention, exposing major exporters and importers of non-renewable groundwater, and thus help explore solutions to improve the sustainability of global food supply.

  18. Reviews.

    Science.gov (United States)

    Journal of Chemical Education, 1988

    1988-01-01

    Reviews three computer software packages for chemistry education including "Osmosis and Diffusion" and "E.M.E. Titration Lab" for Apple II and "Simplex-V: An Interactive Computer Program for Experimental Optimization" for IBM PC. Summary ratings include ease of use, content, pedagogic value, student reaction, and…

  19. Reviews

    NARCIS (Netherlands)

    Sleumer, H.; Steenis, van C.G.G.J.

    1966-01-01

    An exhaustive Flora of Delhi, compiled by J. K. Maheshwari, was published by C.S.I.R. in 1963 (for a review see Blumea 13, 1965, p. 174). During the compilation of that flora, 278 line-drawings, illustrating the habits and chief features of the plants found in Delhi, were prepared; they form a welco

  20. Reviews

    NARCIS (Netherlands)

    NN,

    1998-01-01

    BALGOOY, M.M.J, VAN. 1998. Malesian Seed Plants. Volume 2. Portraits of tree families. 307 pp., numerous text figures. Published by Rijksherbarium/Hortus Botanicus, Leiden. ISBN 90-71236-36-6. Paperback. Price: NLG 100.00. This is the second volume of a trilogy [see the review of ‘Spot-characters’ b

  1. Reviews.

    Science.gov (United States)

    Repak, Arthur J.; And Others

    1988-01-01

    Computer software, audiovisuals, and books are reviewed. Includes topics on interfacing, ionic equilibrium, space, the classification system, Acquired Immune Disease Syndrome, evolution, human body processes, energy, pesticides, teaching school, cells, and geological aspects. Availability, price, and a description of each are provided. (RT)

  2. Review

    DEFF Research Database (Denmark)

    Van Den Hazel, H B; Kielland-Brandt, Morten; Winther, Jakob R.

    1996-01-01

    The yeast vacuole, which is equivalent to the lysosome of higher eukaryotes, is one of the best characterized degradative organelles. This review describes the biosynthesis and function of yeast vacuolar proteases. Most of these enzymes are delivered to the vacuole via the early compartments...

  3. Review

    NARCIS (Netherlands)

    Wilde, de W.J.J.O.

    1994-01-01

    This review marks the appearance of Volume II, after the publication of Volume I, Pteridophytes and Gymnosperms, in 1990; several more volumes are expected in the future before completion of the Vascular plants as a whole. The present volume contains 73 families out of some 250-500 families which ca

  4. Reviews

    NARCIS (Netherlands)

    Adema, Frits

    1995-01-01

    This is the second volume of a revision of Tabernaemontana (Apocynaceae). The volume covers the New World species (44) and the genus Stemmadenia (10 species). This part of the revision of Tabernaemontana comes up to the high standards set in the first volume [see the review by Leenhouts, Blumea 38 (

  5. Complexed iron removal from groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Munter, R.; Ojaste, H.; Sutt, J. [Tallinn Technical University, Tallinn (Estonia). Dept. of Environmental & Chemical Technology

    2005-07-01

    The paper demonstrates an intensive work carried out and results obtained on the pilot plant of the City of Kogalym Water Treatment Station (Tjumen, Siberia, Russian Federation) to elaborate on a contemporary nonreagent treatment technology for the local iron-rich groundwater. Several filter materials (Birm, Pyrolox, hydroanthracite, Everzit, granulated activated carbon) and chemical oxidants (ozone, chlorine, hydrogen peroxide, oxygen, and potassium permanganate) were tested to solve the problem with complexed iron removal from groundwater. The final elaborated technology consists of raw water intensive aeration in the gas-degas treatment unit followed by sequential filtration through hydroanthracite and the special anthracite Everzit.

  6. AUTOMATING GROUNDWATER SAMPLING AT HANFORD

    Energy Technology Data Exchange (ETDEWEB)

    CONNELL CW; HILDEBRAND RD; CONLEY SF; CUNNINGHAM DE

    2009-01-16

    Until this past October, Fluor Hanford managed Hanford's integrated groundwater program for the U.S. Department of Energy (DOE). With the new contract awards at the Site, however, the CH2M HILL Plateau Remediation Company (CHPRC) has assumed responsibility for the groundwater-monitoring programs at the 586-square-mile reservation in southeastern Washington State. These programs are regulated by the Resource Conservation and Recovery Act (RCRA) and the Comprehensive Environmental Response Compensation and Liability Act (CERCLA). The purpose of monitoring is to track existing groundwater contamination from past practices, as well as other potential contamination that might originate from RCRA treatment, storage, and disposal (TSD) facilities. An integral part of the groundwater-monitoring program involves taking samples of the groundwater and measuring the water levels in wells scattered across the site. More than 1,200 wells are sampled each year. Historically, field personnel or 'samplers' have been issued pre-printed forms that have information about the well(s) for a particular sampling evolution. This information is taken from the Hanford Well Information System (HWIS) and the Hanford Environmental Information System (HEIS)--official electronic databases. The samplers used these hardcopy forms to document the groundwater samples and well water-levels. After recording the entries in the field, the samplers turned the forms in at the end of the day and the collected information was posted onto a spreadsheet that was then printed and included in a log book. The log book was then used to make manual entries of the new information into the software application(s) for the HEIS and HWIS databases. This is a pilot project for automating this tedious process by providing an electronic tool for automating water-level measurements and groundwater field-sampling activities. The automation will eliminate the manual forms and associated data entry, improve the

  7. Groundwater and Terrestrial Water Storage

    Science.gov (United States)

    Rodell, Matthew; Chambers, Don P.; Famiglietti, James S.

    2014-01-01

    Terrestrial water storage (TWS) comprises groundwater, soil moisture, surface water, snow,and ice. Groundwater typically varies more slowly than the other TWS components because itis not in direct contact with the atmosphere, but often it has a larger range of variability onmultiannual timescales (Rodell and Famiglietti, 2001; Alley et al., 2002). In situ groundwaterdata are only archived and made available by a few countries. However, monthly TWSvariations observed by the Gravity Recovery and Climate Experiment (GRACE; Tapley et al.,2004) satellite mission, which launched in 2002, are a reasonable proxy for unconfinedgroundwater at climatic scales.

  8. Oak Ridge National Laboratory Review

    Energy Technology Data Exchange (ETDEWEB)

    Krause, C.; Robinson, C.; Zucker, A.; Aaron, M. (eds.)

    1991-01-01

    This review covers some areas of research at ORNL. Topics presented are the high-temperature superconductivity pilot center, superconductivity research successes, superconducting motors, waste site remediation, groundwater contamination, and enzymes for extracting energy from trash. (GHH)

  9. Psychosocial and demographic predictors of adherence and non-adherence to health advice accompanying air quality warning systems: a systematic review.

    Science.gov (United States)

    D'Antoni, Donatella; Smith, Louise; Auyeung, Vivian; Weinman, John

    2017-09-22

    Although evidence shows that poor air quality can harm human health, we have a limited understanding about the behavioural impact of air quality forecasts. Our aim was to understand to what extent air quality warning systems influence protective behaviours in the general public, and to identify the demographic and psychosocial factors associated with adherence and non-adherence to the health advice accompanying these warnings. In August 2016 literature was systematically reviewed to find studies assessing intended or actual adherence to health advice accompanying air quality warning systems, and encouraging people to reduce exposure to air pollution. Predictors of adherence to the health advice and/or self-reported reasons for adherence or non-adherence were also systematically reviewed. Studies were included only if they involved participants who were using or were aware of these warning systems. Studies investigating only protective behaviours due to subjective perception of bad air quality alone were excluded. The results were narratively synthesised and discussed within the COM-B theoretical framework. Twenty-one studies were included in the review: seventeen investigated actual adherence; three investigated intended adherence; one assessed both. Actual adherence to the advice to reduce or reschedule outdoor activities during poor air quality episodes ranged from 9.7% to 57% (Median = 31%), whereas adherence to a wider range of protective behaviours (e.g. avoiding busy roads, taking preventative medication) ranged from 17.7% to 98.1% (Median = 46%). Demographic factors did not consistently predict adherence. However, several psychosocial facilitators of adherence were identified. These include knowledge on where to check air quality indices, beliefs that one's symptoms were due to air pollution, perceived severity of air pollution, and receiving advice from health care professionals. Barriers to adherence included: lack of understanding of the indices

  10. Detecting small groundwater discharge springs using handheld thermal infrared imagery.

    Science.gov (United States)

    Röper, Tania; Greskowiak, Janek; Massmann, Gudrun

    2014-01-01

    Ground-based handheld thermal infrared imagery was used for the detection of small-scale groundwater springs at the northwestern beach of Spiekeroog Island (northwest Germany). The surveys and in situ measurements of electric conductivity were carried out from shortly before to shortly after low tide along the low water line. Several brackish groundwater discharge springs with a diameter of 1-2 cm were observed along the beach at a distance of 2-3 m above the low water line. The high fresh water portion in the discharging water derives from the fresh water lens in the center of the island. During cold weather, the springs were identified by a significantly increased temperature (3-5 °C higher) and a lower electric conductivity (30 mS/cm). During warmer weather conditions, an inverse temperature contrast was observed. The measurements confirm the applicability of thermal imagery for the detection of small-scale groundwater discharge locations as an extension to the established method of aerial thermal scans and prove the existence of submarine groundwater seeps in porous systems. A ground-based handheld thermal infrared imagery survey enables a precise installation of sampling devices as, for example, seepage meters. © 2013, National Ground Water Association.

  11. Mapping groundwater quality in the Netherlands

    NARCIS (Netherlands)

    Pebesma, Edzer Jan

    2001-01-01

    Groundwater quality is the suitability of groundwater for a certain purpose (e.g. for human consumption), and is mostly determined by its chemical composition. Pollution from agricultural and industrial origin threatens the groundwater quality in the Netherlands. Locally, this pollution is me

  12. Groundwater: Illinois' Buried Treasure. Education Activity Guide.

    Science.gov (United States)

    Environmental Education Association of Illinois, Chicago.

    Groundwater is an extremely valuable resource that many feel has been too long neglected and taken for granted. There is growing recognition in Illinois and throughout the United States that comprehensive groundwater protection measures are vital. Illinois embarked on a course in protecting groundwater resources with the passage of the Illinois…

  13. Geochemical modelling baseline compositions of groundwater

    DEFF Research Database (Denmark)

    Postma, Diederik Jan; Kjøller, Claus; Andersen, Martin Søgaard

    2008-01-01

    Reactive transport models, were developed to explore the evolution in groundwater chemistry along the flow path in three aquifers; the Triassic East Midland aquifer (UK), the Miocene aquifer at Valreas (F) and the Cretaceous aquifer near Aveiro (P). All three aquifers contain very old groundwaters...... of the evolution in natural baseline properties in groundwater....

  14. Groundwater: Illinois' Buried Treasure. Education Activity Guide.

    Science.gov (United States)

    Environmental Education Association of Illinois, Chicago.

    Groundwater is an extremely valuable resource that many feel has been too long neglected and taken for granted. There is growing recognition in Illinois and throughout the United States that comprehensive groundwater protection measures are vital. Illinois embarked on a course in protecting groundwater resources with the passage of the Illinois…

  15. Detection and Remediation of Groundwater Pollution

    Institute of Scientific and Technical Information of China (English)

    王杰

    2016-01-01

    Groundwater is an important part of the water cycle and is also widely used as sources of drinking water. With the increasing de?velopment of groundwater exploitation, the pollution is becoming more and more serious. This paper talks about the main research direc?tions of groundwater pollution, the detection, the remediation and some conclusions.

  16. Groundwater and geothermal: urban district heating applications

    Energy Technology Data Exchange (ETDEWEB)

    Mounts, R.; Frazier, A.; Wood, E.; Pyles, O.

    1982-01-01

    This report describes how several cities use groundwater and geothermal energy in district heating systems. It begins with groundwater, introducing the basic technology and techniques of development, and describing two case studies of cities with groundwater-based district heating systems. The second half of the report consists of three case studies of cities with district heating systems using higher temperature geothermal resources.

  17. State space modeling of groundwater fluctuations

    NARCIS (Netherlands)

    Berendrecht, W.L.

    2004-01-01

    Groundwater plays an important role in both urban and rural areas. It is therefore essential to monitor groundwater fluctuations. However, data that becomes available need to be analyzed further in order to extract specific information on the groundwater system. Until recently, simple linear time se

  18. The state of antimicrobial resistance surveillance in the military health system: a review of improvements made in the last 10 years and remaining surveillance gaps.

    Science.gov (United States)

    Chandrasekera, Ruvani M; Lesho, Emil P; Chukwuma, Uzo; Cummings, James F; Waterman, Paige E

    2015-02-01

    During a military public health laboratory symposium held in 1999, concerns were raised that the military health system lacked a standardized antimicrobial resistance (AMR) surveillance system that allowed comparison of data across sites, investigation of trends, and understanding of resistance mechanisms. The purpose of this review was to assess if current AMR activities in the military health system have addressed the aforementioned gaps. It was determined that much progress has already been made within the Department of Defense with respect to monitoring and understanding AMR through initiatives such as the Antimicrobial Resistance Monitoring and Research Program-a strong Department of Defense-wide surveillance program. These surveillance efforts can be made more robust through harmonization of testing and reporting structures across military treatment facilities, and by encouraging military treatment facility participation. Reprint & Copyright © 2015 Association of Military Surgeons of the U.S.

  19. SCANS (Shipping Cask ANalysis System) a microcomputer-based analysis system for shipping cask design review: User`s manual to Version 3a. Volume 1, Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Mok, G.C.; Thomas, G.R.; Gerhard, M.A.; Trummer, D.J.; Johnson, G.L. [Lawrence Livermore National Lab., CA (United States)

    1998-03-01

    SCANS (Shipping Cask ANalysis System) is a microcomputer-based system of computer programs and databases developed at the Lawrence Livermore National Laboratory (LLNL) for evaluating safety analysis reports on spent fuel shipping casks. SCANS is an easy-to-use system that calculates the global response to impact loads, pressure loads and thermal conditions, providing reviewers with an independent check on analyses submitted by licensees. SCANS is based on microcomputers compatible with the IBM-PC family of computers. The system is composed of a series of menus, input programs, cask analysis programs, and output display programs. All data is entered through fill-in-the-blank input screens that contain descriptive data requests. Analysis options are based on regulatory cases described in the Code of Federal Regulations 10 CFR 71 and Regulatory Guides published by the US Nuclear Regulatory Commission in 1977 and 1978.

  20. Reviews

    Directory of Open Access Journals (Sweden)

    Wilma D'Ambrosio

    2013-12-01

    Full Text Available In the wake of the great interest raised by Maurizio Gabrieli’s review of the book Musical Networks. Parallel Distributed Perception and Performance (various authors; edited by Niall Griffith and Peter M. Todd, MA: MIT Press, Cambridge, 1999 which appeared in our last issue of Analitica, the present review section no longer follows the format used up to now but offers a survey of texts dedicated to the relationship between music analysis and technology. This decision was also made as a result of the request for more information on the subject by many of our readers. In coming issues we plan to extend this bibliography and comment on at least some of the most interesting texts published in recent years, among which we would immediately like to draw attention to the important work by Baroni, Dalmonte and Jacoboni published in 1999 (Le regole della musica. Indagine sui meccanismi della comunicazione, Torino, I Manuali EDT/SIdM, 1999.

  1. Reviews

    Directory of Open Access Journals (Sweden)

    Philip Barker

    1998-12-01

    Full Text Available There were two copy-editing blunders in Clive Betts's review, in ALT-J 5 (3, of Shirley Fletcher's Designing Competence-Based Training, one in paragraph 2 line 1, the other in paragraph 3 line 8. The errors (the result of the Editor, Gabriel Jacobs, trying to perform a final proof of the journal at lightning speed in order to meet the printing deadline, and not of any mistake on the part of either Philip Barker or the University of Wales Press hardly affected meaning, but the fact that they appeared in a review of a book on competence makes the embarrassment all the more telling. The Editor apologizes, and thanks eagle-eyed readers. He has decided to read the book in the hope that such errors will not recur.

  2. Directions for social research to underpin improved groundwater management

    Science.gov (United States)

    Mitchell, Michael; Curtis, Allan; Sharp, Emily; Mendham, Emily

    2012-07-01

    SummaryImprovements in groundwater management require strategies to change human behaviour, yet there has been limited social research in the broad arena of groundwater management. This paper provides a critical review of the small but expanding literature on that topic to identify future directions for social researchers. Comprehensive search methods identified almost three hundred potentially relevant publications, which were sorted thematically and assessed in terms of their theoretical underpinning and the evidence used to support key findings. This process enabled the authors to identify a small number of high quality publications and to identify future research opportunities. The latter includes analysing how concepts of risk and sustainable yield are constructed differently by stakeholders, especially related to divisive issues concerning coal seam gas developments and reforms that reduce irrigation allocations; how governance arrangements can be improved to achieve more effective collaborative management of groundwater, especially if managed aquifer recharge is to be more widely implemented in rural agricultural contexts; and the role that trust and social norms can play in changing groundwater use practices.

  3. Remediation alternatives for low-level herbicide contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    Conger, R.M. [BASF Corp., Geismar, LA (United States)

    1995-10-01

    In early 1995, an evaluation of alternatives for remediation of a shallow groundwater plume containing low-levels of an organic herbicide was conducted at BASF Corporation, a petrochemical facility located in Ascension Parish, Louisiana. The contaminated site is located on an undeveloped portion of property within 1/4 mile of the east bank of the Mississippi River near the community of Geismar. Environmental assessment data indicated that about two acres of the thirty acre site had been contaminated from past waste management practices with the herbicide bentazon. Shallow soils and groundwater between 5 to 15 feet in depth were affected. Maximum concentrations of bentazon in groundwater were less than seven parts per million. To identify potentially feasible remediation alternatives, the environmental assessment data, available research, and cost effectiveness were reviewed. After consideration of a preliminary list of alternatives, only two potentially feasible alternatives could be identified. Groundwater pumping, the most commonly used remediation alternative, followed by carbon adsorption treatment was identified as was a new innovative alternative known as vegetative transpiration. This alternative relies on the natural transpiration processes of vegetation to bioremediate organic contaminants. Advantages identified during screening suggest that the transpiration method could be the best remediation alternative to address both economic and environmental factors. An experiment to test critical factors of the vegetatived transpiration alternative with bentazon was recommended before a final decision on feasibility can be made.

  4. Uranium in groundwater--Fertilizers versus geogenic sources.

    Science.gov (United States)

    Liesch, Tanja; Hinrichsen, Sören; Goldscheider, Nico

    2015-12-01

    Due to its radiological and toxicological properties even at low concentration levels, uranium is increasingly recognized as relevant contaminant in drinking water from aquifers. Uranium originates from different sources, including natural or geogenic, mining and industrial activities, and fertilizers in agriculture. The goal of this study was to obtain insights into the origin of uranium in groundwater while differentiating between geogenic sources and fertilizers. A literature review concerning the sources and geochemical processes affecting the occurrence and distribution of uranium in the lithosphere, pedosphere and hydrosphere provided the background for the evaluation of data on uranium in groundwater at regional scale. The state of Baden-Württemberg, Germany, was selected for this study, because of its hydrogeological and land-use diversity, and for reasons of data availability. Uranium and other parameters from N=1935 groundwater monitoring sites were analyzed statistically and geospatially. Results show that (i) 1.6% of all water samples exceed the German legal limit for drinking water (10 μg/L); (ii) The range and spatial distribution of uranium and occasional peak values seem to be related to geogenic sources; (iii) There is a clear relation between agricultural land-use and low-level uranium concentrations, indicating that fertilizers generate a measurable but low background of uranium in groundwater.

  5. Global Groundwater related Risk Indicators: quantifying groundwater stress and groundwater table decline (1990-2010) at global scale

    Science.gov (United States)

    Faneca Sanchez, Marta; Sutanudjaja, Edwin; Kuijper, Marijn; Bierkens, Marc

    2016-04-01

    Groundwater is an invisible but indispensable resource for the economic development of many countries. Due to the need for this resource, in many cases it is exploited under severe pressure and the exploitation can become not sustainable. The non-sustainable exploitation of water is a well-known problem on both regional and global scales. However, most currently-available assessments on water stress still mostly focus on surface water and on water balances. In this work, we presented two global maps of groundwater risk indicators: an updated version of the groundwater stress (Gleeson et al., 2011, DOI: 10.1038/nature11295) and an indicator on groundwater table decline for the period 1990-2010. To calculate both indicators, we used the updated PCR-GLOBWB model output at 5 arcmin resolution (about 10 km at the equator), that is extended with an offline coupling to a global groundwater MODFLOW model. PCR-GLOBWB simulates daily river discharge and groundwater recharge, as well as surface water and groundwater abstraction rates. The latter are estimated internally within the model based on the simulation of their availabilities and water demands for irrigation and other sectors. The daily output of PCR-GLOBWB would then be aggregated to the monthly resolution and used to force the MODFLOW groundwater model resolving spatio-temporal groundwater table dynamics, incorporating the simulated groundwater abstraction of PCR-GLOBWB. Using the PCR-GLOBWB and MODFLOW simulation results from the period 1990-2010, we then quantified groundwater stress and assessed the groundwater table decline. Results are presented on four different spatial scales: 5 arcmin pixel, drainage/sub-catchment unit, state level, and major aquifer unit. The maps clearly show where groundwater is under stress, where there is a trend in the drop of the groundwater table, the slope of the drop and the significance of it.

  6. Groundwater regulation and integrated planning

    Science.gov (United States)

    Quevauviller, Philippe; Batelaan, Okke; Hunt, Randall J.

    2016-01-01

    The complex nature of groundwater and the diversity of uses and environmental interactions call for emerging groundwater problems to be addressed through integrated management and planning approaches. Planning requires different levels of integration dealing with: the hydrologic cycle (the physical process) including the temporal dimension; river basins and aquifers (spatial integration); socioeconomic considerations at regional, national and international levels; and scientific knowledge. The great natural variation in groundwater conditions obviously affects planning needs and options as well as perceptions from highly localised to regionally-based approaches. The scale at which planning is done therefore needs to be carefully evaluated against available policy choices and options in each particular setting. A solid planning approach is based on River Basin Management Planning (RBMP), which covers: (1) objectives that management planning are designed to address; (2) the way various types of measures fit into the overall management planning; and (3) the criteria against which the success or failure of specific strategies or interventions can be evaluated (e.g. compliance with environmental quality standards). A management planning framework is to be conceived as a “living” or iterated document that can be updated, refined and if necessary changed as information and experience are gained. This chapter discusses these aspects, providing an insight into European Union (EU), United States and Australia groundwater planning practices.

  7. Groundwater Resources: Investigation and Development

    Science.gov (United States)

    Anderson, Mary P.

    A glance through the table of contents of this volume might suggest that it is yet another introductory text on principles of groundwater hydrology. All of the usual basic topics are covered including definitions of terms and concepts, aquifer types, drilling methods, and pumping tests. But partly because this book is intended for practicing groundwater consultants rather than students, other less elementary topics such as environmental isotope techniques, geochemical methods, interpretation and utilization of spring flow, geophysical methods, and groundwater balances are also included.According to the preface, ‘practical applicability’ is stressed ‘to show how groundwater investigations should be conducted using a systematic, well-directed effort’ and to describe ‘… what to do, what to avoid, and what kind of results one can reasonably expect …’ While this book was published as part of a series of monographs on water pollution, it is more in the nature of a handbook than a true monograph. That is, it is not an in-depth treatment of a single topic but presents a broad introduction to the ways in

  8. Adsorptive Iron Removal from Groundwater

    NARCIS (Netherlands)

    Sharma, S.K.

    2001-01-01

    Iron is commonly present in groundwater worldwide. The presence of iron in drinking water is not harmful to human health, however it is undesirable because of the associated aesthetic and operational problems, namely: bad taste, colour, stains on laundry and plumbing fixtures, and aftergrowth in the

  9. Adsorptive iron removal from groundwater

    NARCIS (Netherlands)

    Sharma, S.K.

    2001-01-01

    Iron is commonly present in groundwater worldwide. The presence of iron in the water supply is not harmful to human health, however it is undesirable. Bad taste, discoloration, staining, deposition in the distribution system leading to aftergrowth, and incidences of high turbidity are some

  10. Solid-state reactions during mechanical alloying of ternary Fe–Al–X (X=Ni, Mn, Cu, Ti, Cr, B, Si) systems: A review

    Energy Technology Data Exchange (ETDEWEB)

    Hadef, Fatma, E-mail: hadef77@yahoo.fr [Laboratoire de Recherche sur la Physico-Chimie des Surfaces et Interfaces, LRPCSI, Université 20 Août 1955, BP 26, Route d’El-Haddaiek, Skikda 21000 (Algeria); Département de Physique, Faculté des Sciences, Université 20 Août 1955, BP 26, Route d’El-Haddaiek, Skikda 21000 (Algeria)

    2016-12-01

    The last decade has witnessed an intensive research in the field of nanocrystalline materials due to their enhanced properties. A lot of processing techniques were developed in order to synthesis these novel materials, among them mechanical alloying or high-energy ball milling. In fact, mechanical alloying is one of the most common operations in the processing of solids. It can be used to quickly and easily synthesize a variety of technologically useful materials which are very difficult to manufacture by other techniques. One advantage of MA over many other techniques is that is a solid state technique and consequently problems associated with melting and solidification are bypassed. Special attention is being paid to the synthesis of alloys through reactions mainly occurring in solid state in many metallic ternary Fe–Al–X systems, in order to improve mainly Fe–Al structural and mechanical properties. The results show that nanocrystallization is the common result occurring in all systems during MA process. The aim of this work is to illustrate the uniqueness of MA process to induce phase transformation in metallic Fe–Al–X (X=Ni, Mn, Cu, Ti, Cr, B, Si) systems. - Highlights: • A review of state of the art on binary Fe–Al alloys was presented. • Structural and microstructural properties of MA ternary Fe–Al–X alloys were summerized. • MA process is a powerful tool for producing metallic alloys at the nanometer scale.

  11. Rational design of liposomal drug delivery systems, a review: Combined experimental and computational studies of lipid membranes, liposomes and their PEGylation.

    Science.gov (United States)

    Bunker, Alex; Magarkar, Aniket; Viitala, Tapani

    2016-10-01

    Combined experimental and computational studies of lipid membranes and liposomes, with the aim to attain mechanistic understanding, result in a synergy that makes possible the rational design of liposomal drug delivery system (LDS) based therapies. The LDS is the leading form of nanoscale drug delivery platform, an avenue in drug research, known as "nanomedicine", that holds the promise to transcend the current paradigm of drug development that has led to diminishing returns. Unfortunately this field of research has, so far, been far more successful in generating publications than new drug therapies. This partly results from the trial and error based methodologies used. We discuss experimental techniques capable of obtaining mechanistic insight into LDS structure and behavior. Insight obtained purely experimentally is, however, limited; computational modeling using molecular dynamics simulation can provide insight not otherwise available. We review computational research, that makes use of the multiscale modeling paradigm, simulating the phospholipid membrane with all atom resolution and the entire liposome with coarse grained models. We discuss in greater detail the computational modeling of liposome PEGylation. Overall, we wish to convey the power that lies in the combined use of experimental and computational methodologies; we hope to provide a roadmap for the rational design of LDS based therapies. Computational modeling is able to provide mechanistic insight that explains the context of experimental results and can also take the lead and inspire new directions for experimental research into LDS development. This article is part of a Special Issue entitled: Biosimulations edited by Ilpo Vattulainen and Tomasz Róg.

  12. Temporal variations of groundwater salinity and temperature in a tidal flat in front of a tide pool

    Science.gov (United States)

    Nakashita, Shinya; Hibino, Tadashi; Komai, Katsuaki; Narong, Touch

    2016-07-01

    A tidal flat in an estuary is a complex hydrological system, which is characterized by interactions between surface water in river and groundwater and is particularly driven by tides. Small-scale variability in the discharge or inflow could lead to variable results of surface groundwater salinity and temperature. In particular, there is a high possibility that a hydraulic head difference due to the presence of a tide pool, lagoon, or seep would cause the generation of small-scale spatial submarine groundwater discharge. This study investigates the spatio-temporal variations in surface groundwater salinity and temperature (0-50 cm depth) and the groundwater table in a tidal flat in the presence and absence of a tide pool. A tide pool formed in the Ota River diversion channel at the study observation site following the construction of a masonry revetment in the intertidal zone. We established observation sites at three locations to consider the effects of the presence or absence of a tide pool. Specifically, we measured the surface water in river and groundwater salinity, temperature, and level in the presence and absence of a tide pool in 2007 and 2009. Reviewing the past data based on these results, we found the characteristic variation of groundwater salinity around the tide pool during flood event in 2004. Groundwater salinity and temperature were directly measured by setting conductivity-temperature meters in the tidal flat. We conclude that the groundwater table in the presence of the tide pool was 20 cm higher than in areas where no tide pool existed. The temporal variation of groundwater salinity in the presence of the tide pool was 5 psu lower than those where a tide pool was absent. Moreover, we confirmed the increase in groundwater salinity up to 8 psu in the tidal flat during flood, when river water salinity was at 0 psu and groundwater salinity in the tide pool was at 10 psu. We consider that the high groundwater table, the low salinity, and the increase

  13. A synthesis of hydrochemistry with an integrated conceptual model for groundwater in the Hexi Corridor, northwestern China

    Science.gov (United States)

    Wang, Liheng; Dong, Yanhui; Xu, Zhifang

    2017-09-01

    Although many studies have investigated the recharge and evolution of groundwater in the Hexi Corridor, northwestern (NW) China, they describe individual sites such as Jinchang, Jiuquan, Dunhuang, and others. Considering the similarity of these sites, a systematic review of the entire Hexi Corridor is lacking. This paper compares and summarizes previous studies in the Hexi Corridor to provide a regional perspective of the isotopic characteristics and hydrochemical composition of groundwater. In unconfined aquifers, groundwater is recharged by snow and ice melt water from the Qilian Mountains; local precipitation can be neglected. Therefore, the groundwater belongs to a unique hydrological cycle model in the Hexi Corridor, referred to as snow and ice melt water-groundwater system. The dominant anion species changes from HCO3- in front of the mountains to SO42- in the middle basin and Cl- at the basin boundary along the groundwater flow direction, and TDS increases gradually owing to evaporation. A major hydrogeochemical process is the dissolution of minerals from the aquifer in the recharge area changing to cation exchange reactions in the discharge area. Confined groundwater was recharged mainly in the late Pleistocene and middle Holocene at colder temperatures than those of modern times; thus, it is non-renewable. In addition to dissolution, the hydrochemical composition of confined groundwater is also affected by cation exchange reactions. The hydrogeochemical categories of the confined groundwater are simple and stable. In the present study, a conceptual model is established on the basis of the analyses presented, which has important implications for water resource management in the Hexi Corridor. The inter-basin water allocation program should continue in order to achieve optimal utilization of water resources, but groundwater exploitation should be limited as much as possible. Additionally, on the basis of the review and integration of previous research, the

  14. Quantifying renewable groundwater stress with GRACE

    Science.gov (United States)

    Richey, Alexandra S.; Thomas, Brian F.; Lo, Min‐Hui; Reager, John T.; Voss, Katalyn; Swenson, Sean; Rodell, Matthew

    2015-01-01

    Abstract Groundwater is an increasingly important water supply source globally. Understanding the amount of groundwater used versus the volume available is crucial to evaluate future water availability. We present a groundwater stress assessment to quantify the relationship between groundwater use and availability in the world's 37 largest aquifer systems. We quantify stress according to a ratio of groundwater use to availability, which we call the Renewable Groundwater Stress ratio. The impact of quantifying groundwater use based on nationally reported groundwater withdrawal statistics is compared to a novel approach to quantify use based on remote sensing observations from the Gravity Recovery and Climate Experiment (GRACE) satellite mission. Four characteristic stress regimes are defined: Overstressed, Variable Stress, Human‐dominated Stress, and Unstressed. The regimes are a function of the sign of use (positive or negative) and the sign of groundwater availability, defined as mean annual recharge. The ability to mitigate and adapt to stressed conditions, where use exceeds sustainable water availability, is a function of economic capacity and land use patterns. Therefore, we qualitatively explore the relationship between stress and anthropogenic biomes. We find that estimates of groundwater stress based on withdrawal statistics are unable to capture the range of characteristic stress regimes, especially in regions dominated by sparsely populated biome types with limited cropland. GRACE‐based estimates of use and stress can holistically quantify the impact of groundwater use on stress, resulting in both greater magnitudes of stress and more variability of stress between regions. PMID:26900185

  15. Trend Analyses of Nitrate in Danish Groundwater

    Science.gov (United States)

    Hansen, B.; Thorling, L.; Dalgaard, T.; Erlandsen, M.

    2012-04-01

    This presentation assesses the long-term development in the oxic groundwater nitrate concentration and nitrogen (N) loss due to intensive farming in Denmark. Firstly, up to 20-year time-series from the national groundwater monitoring network enable a statistically systematic analysis of distribution, trends and trend reversals in the groundwater nitrate concentration. Secondly, knowledge about the N surplus in Danish agriculture since 1950 is used as an indicator of the potential loss of N. Thirdly, groundwater recharge CFC (Chlorofluorocarbon) age determination allows linking of the first two dataset. The development in the nitrate concentration of oxic groundwater clearly mirrors the development in the national agricultural N surplus, and a corresponding trend reversal is found in groundwater. Regulation and technical improvements in the intensive farming in Denmark have succeeded in decreasing the N surplus by 40% since the mid 1980s while at the same time maintaining crop yields and increasing the animal production of especially pigs. Trend analyses prove that the youngest (0-15 years old) oxic groundwater shows more pronounced significant downward nitrate trends (44%) than the oldest (25-50 years old) oxic groundwater (9%). This amounts to clear evidence of the effect of reduced nitrate leaching on groundwater nitrate concentrations in Denmark. Are the Danish groundwater monitoring strategy obtimal for detection of nitrate trends? Will the nitrate concentrations in Danish groundwater continue to decrease or are the Danish nitrate concentration levels now appropriate according to the Water Framework Directive?

  16. Thermal management of an urban groundwater body

    Directory of Open Access Journals (Sweden)

    J. Epting

    2012-06-01

    Full Text Available This study presents a management concept for the sustainable thermal use of an urban groundwater body. The concept is designed to be applied for shallow thermal groundwater use and is based on (1 a characterization of the present thermal state of the investigated urban groundwater body; (2 the definition of development goals for specific aquifer regions, including future aquifer use and urbanization; and (3 an evaluation of the thermal use potential for these regions.

    The investigations conducted in the city of Basel (Switzerland focus on thermal processes down-gradient of thermal groundwater use, effects of heated buildings in the aquifer as well as the thermal influence of river-groundwater interaction. Investigation methods include: (1 short- and long-term data analysis; (2 high-resolution multilevel groundwater temperature monitoring; as well as (3 3-D numerical groundwater flow and heat-transport modeling and scenario development. The combination of these methods allows quantifying the thermal influence on the investigated urban groundwater body, including the influences of thermal groundwater use and additional heat from urbanization. Subsequently, management strategies for minimizing further groundwater temperature increase, targeting "potential natural" groundwater temperatures for specific aquifer regions and exploiting the thermal use potential are discussed.

  17. Applicability of ELISA-based Determination of Pesticides for Groundwater Quality Monitoring

    Science.gov (United States)

    Tsuchihara, Takeo; Yoshimoto, Shuhei; Ishida, Satoshi; Imaizumi, Masayuki

    The principals and procedures of ELISA (Enzyme-linked Immunosorbent Assay)-based determination of pesticides (Fenitrothion) in environmental samples were reviewed, and the applicability of the ELISA method for groundwater quality monitoring were validated through the experimental tracer tests in soil columns and the field test in Okinoerabu Island. The test results showed that the ELISA method could be useful not only for screening but also for quantitative analysis of pesticides. In the experimental tracer tests in soil columns, the retardation of pesticides leaching compared with conservative tracers were observed. In the field test, the contamination of the pesticide was detected in groundwater samples in Okinoerabu Island, even though the targeted pesticide was considered to be applied to the upland field 4 months ago. In order to investigate the transport and fate of pesticides in groundwater taking into account retardation from the field to groundwater table and the residue in groundwater, continuous observations of pesticides in groundwater are in a strong need, and the ELISA method is applicable to the long-term quality groundwater monitoring.

  18. Reviews

    Directory of Open Access Journals (Sweden)

    Philip Barker

    1997-12-01

    Full Text Available For a variety of different reasons, increasing use is now being made of the Internet for the delivery of course materials and/or for the support of teaching and learning activities. The details of the mechanisms used will obviously vary from one situation to another, depending upon the types of problem to be addressed. These may involve mentoring, teaching, monitoring, recording, tutoring, assessing, and so on. In this book, the author attempts to review the educational and administrative considerations of offering courses, course materials or course delivery via the Internet.

  19. Rapid Discrimination of Malignant Breast Lesions from Normal Tissues Utilizing Raman Spectroscopy System: A Systematic Review and Meta-Analysis of In Vitro Studies.

    Science.gov (United States)

    Deng, Ke; Zhu, Chenjing; Ma, Xuelei; Jia, Hongyuan; Wei, Zhigong; Xiao, Yue; Xu, Jing

    2016-01-01

    The aim of this study is to evaluate the diagnostic accuracy of Raman spectroscopy system in the detection of malignant breast lesions through a systemic review and meta-analysis of published studies. We conducted a comprehensive literature search of PubMed and Embase from 2000 to June 2015. Published studies that evaluated the diagnostic performance of Raman spectroscopy in distinguishing malignant breast lesions from benign lesions and normal tissues were included in our study. The pooled sensitivity, specificity, diagnostic odds ratio, and the area under the curve of summary receiver-operating characteristic curves was derived. A Revised Tool for the Quality Assessment of Diagnostic Accuracy Studies guidelines was used to assess the quality of included studies. The initial search produced a total of 157 articles after removing duplicates. Nine studies (8 in vitro and 1 in vivo) were eligible in this meta-analysis. We analyzed the eight in vitro studies with 1756 lesions, the pooled sensitivity and specificity of Raman spectroscopy system for the diagnosis of malignant breast lesions were 0.92 (95% CI 0.86-0.96) and 0.97 (97% CI 0.93-0.98), respectively. Diagnostic odds ratio was 266.70 (95% CI 89.38-795.79), and the area under the curve of summary receiver-operating characteristic curves was 0.98 (95% CI 0.97-0.99). Significant heterogeneity was found between studies. There was no evidence of considerable publication bias. Raman spectroscopy system is an optical diagnostic technology with great value for detecting malignant breast lesions. At the same time, it has advantages of being non-invasive, real-time, and easy to use. Thus it deserves to be further explored for intra-operatory breast tumor margin detection.

  20. Shaping the contours of groundwater governance in India

    OpenAIRE

    Kulkarni, Himanshu; Shah, Mihir; P.S. Vijay Shankar

    2015-01-01

    Study region: India. Study focus: India's groundwater dependence and the crises of depletion and contamination of groundwater resources require the development of a robust groundwater dependence framework. Understanding the challenges of developing a groundwater governance framework for regions of extensive groundwater development versus relatively less-developed areas of groundwater development is important. The groundwater typology is a function of both, the hydrogeological aspects of gr...

  1. Water treatment processes in marine recirculating aquaculture systems: A review%海水循环养殖系统水处理工艺综述

    Institute of Scientific and Technical Information of China (English)

    姜妍君; 强志民; 董慧峪; 贲伟伟; 王磊

    2013-01-01

    This paper reviews the key water quality parameters and the related unit treatment processes in marine recirculating aquaculture systems ( RAS). Besides routinely monitoring and controlling salinity, pH, temperature, and dissolved oxygen, RAS usually adopts physical, chemical and biological combinational treatment processes to reduce the concentrations of solid particles, ammonia nitrogen, nitrite, nitrate, organic matter and pathogens. Solid particles can be removed by sedimentation, filtration, foam fractionation or biofiltration according to different particle sizes and settlabilities. Ammonia nitrogen, nitrite and nitrate are mainly removed by biological nitrification and denitrification. Organic matter can be decomposed by microorganisms. Chemical oxidants and ultraviolet radiation are commonly-used disinfection methods in RAS. Disinfectant residue and disinfection byproducts, two critical factors impacting water quality and animal health, should be primarily concerned when selecting appropriate disinfection method. Finally, several commonly-adopted combinational treatment processes for RAS are exemplified with suggestions for future improvement provided.%论述了海水循环养殖系统(RAS)需要控制的水质参数及相关单元水处理工艺.RAS需要对盐度、pH、温度、溶解氧等水质参数进行监测控制,并常采用物理、生物、化学处理的组合工艺,使固体物质、氨氮、亚硝酸盐、硝酸盐、有机物以及致病微生物等的浓度维持在安全范围内.固体物质根据粒径和可沉降性的不同,可采用沉降、过滤、泡沫分离或生物过滤法去除;氨氮、亚硝酸盐以及硝酸盐主要通过生物的硝化和反硝化作用去除;有机物主要通过生物降解去除;化学药剂消毒以及紫外辐照是RAS常用的消毒方法,消毒剂残余及消毒副产物对水质和动物健康的影响是选择合适消毒方法需要考虑的两个关键因素.最后,列举了几种海

  2. Sistema de informações sobre nascidos vivos: um estudo de revisão Brazilian live birth information system: a review study

    Directory of Open Access Journals (Sweden)

    Natália Santana Paiva

    2011-01-01

    Full Text Available O objetivo deste estudo foi realizar uma revisão de literatura sobre o uso do Sistema de Informações sobre Nascidos Vivos (SINASC na pesquisa em saúde. As bases de dados MEDLINE, LILACS e SciELO foram pesquisadas no período de 1994 a 2005, utilizando-se a combinação dos seguintes descritores: "SINASC", "live birth", "Brazil". Foram identificados 157 resumos dentro do período de referência, dos quais 44 foram selecionados e classificados segundo critérios específicos. O número de artigos publicados por ano cresceu ao longo do período estudado. A maioria dos estudos foi desenvolvida na região Sudeste e empregou o município como a unidade geográfica da análise. Uma gama variada de temas foi avaliada, incluindo descrições do perfil de nascidos vivos, avaliações de serviços e programas de saúde e fatores de risco para desfechos infantis. Concluindo, embora o SINASC represente uma fonte de dados importante para a pesquisa sobre a saúde materno-infantil, a cobertura do sistema e a confiabilidade dos seus dados precisam ser melhor avaliadas.The aim of this study was to perform a systematic review of the use of the Live Birth Information System (Sistema de Informações de Nascidos Vivos SINASC in health research. MEDLINE, LILACS and SciELO databases were searched from 1994 to 2005 using the following combination of descriptors: "SINASC", "live birth", "Brazil". We identified 157 abstracts within the reference period, among which 44 were selected and classified according to specific criteria. The number of articles published per year increased during the period studied. The majority of the studies was carried out in the Southeast region and used the municipality as the geographic unity of analysis. A varied range of subjects were assessed including descriptions of live births profiles, health service and programs evaluations and risk factors for infant outcomes. In conclusion, although the SINASC represents an important data

  3. Preliminary hydrogeologic assessment near the boundary of the Antelope Valley and El Mirage Valley groundwater basins, California

    Science.gov (United States)

    Stamos, Christina L.; Christensen, Allen H.; Langenheim, Victoria

    2017-07-19

    structures that could affect groundwater flow between the groundwater basins in the study area, gravity data were collected using more closely spaced measurements in September 2014. Groundwater-level data was gathered and collected from March 2014 through March 2015 to determine depth to water and direction of groundwater flow. The gravity and groundwater-level data showed that the saturated thickness of the alluvium was about 2,000 feet thick to the east and about 130 feet thick above the northward-trending basement ridge near Llano, California. Although it was uncertain whether the basement ridge affects the groundwater system, a potential barrier to groundwater flow could be created if the water table fell below the altitude of the basement ridge, effectively causing the area to the west of the basement ridge to become hydraulically isolated from the area to the east. In addition, the direction of regional-groundwater flow likely will be influenced by future changes in the number and distribution of pumping wells and the thickness of the saturated alluvium from which water is withdrawn. Three-dimensional animations were created to help visualize the relation between the basins’ basement topography and the groundwater system in the area. Further studies that could help to more accurately define the basins and evaluate the groundwater-flow system include exploratory drilling of multi-depth monitoring wells; collection of depth-dependent water-quality samples; and linking together existing, but separate, groundwater-flow models from the Antelope Valley and El Mirage Valley groundwater basins into a single, calibrated groundwater-flow model.

  4. REVIEW

    Directory of Open Access Journals (Sweden)

    N. F. Bugay

    2016-01-01

    Full Text Available Review of Study Guide: «KUBAN STUDIES. KUBAN IN THE XX CENTURY – THE BEGINNING OF THE XXI CENTURY. HISTORY. PEOPLE SOCIETY.» Study Guide (electronic version to grade 11 of educational institutions. A.A. Zaitsev, E.V. Morozova, N.V. Plotichkina and O.A. Borisko, M.A. Egupova, A.B. Sazantovich, I.S. Bashkakov, T.I. Belyaeva. Krasnodar: Perspectives on Education, 2015.In a review of a thorough analysis of all the component parts of the book that will surely attract the attention first of all history teachers and students in 11 classes of educational institutions of the region. A comprehensive presentation of the material significantly adds to the course of modern history of Russia and enrich its specific material about the life of the Russian Cossacks and as part of the – of the Kuban Cossacks. Along with the reference materials of pure nature that is needed for this kind of research are presented and informative sections on the socio-economic condition of the region, the interests of different strata of the population, the multinational factor and the religious beliefs of the population. Cossacks in its warlike mentality, and this trait is passed from generation to generation. But the aspirations of the Cossacks in this respect are transparent – protecting the integrity of the Fatherland, faithful service to him, boundless devotion to the Orthodox faith. The important story is linked with the identity of the Russian Cossacks, its mentality, "Kuban" specificity, especially for the rule on different sections of history, to various of its exponents, both military and civilians. As is known from the Cossacks received a development institute of judging for each Ataman smoking, working village judge. Cossacks series comply with the law as applied his own family, and chic plan – in the state, fought against offenders, it is considered in relation to the Cossacks and representatives of different ethnic communities living with the Cossacks, and

  5. The Savannah River Site`s Groundwater Monitoring Program. First quarter, 1990

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-18

    This report summarizes the Savannah River Site (SRS) groundwater monitoring program conducted in the first quarter of 1990. It includes the analytical data, field data, well activity data, and the other documentation for this program and provides a record of the program`s activities and rationale and an official document of the analytical results. The groundwater monitoring program includes the following activities: installation, maintenance, and abandonment of monitoring wells, environmental soil borings, development of the sampling and analytical schedule, collection and analyses of groundwater samples, review of the analytical data and other data, maintenance of the databases containing groundwater monitoring data and related data, quality assurance (QA) evaluations of laboratory performance, and reports of results to waste-site facility custodians and to the Environmental Protection Section (EPS) of EPD.

  6. The Savannah River Site`s Groundwater Monitoring Program. Fourth quarter, 1990

    Energy Technology Data Exchange (ETDEWEB)

    1991-06-18

    This report summarizes the Savannah River Site (SRS) groundwater monitoring program conducted in the fourth quarter of 1990. It includes the analytical data, field data, well activity data, and other documentation for this program, provides a record of the program`s activities and rationale, and serves as an official document of the analytical results. The groundwater monitoring program includes the following activities: installation, maintenance, and abandonment of monitoring wells, environmental soil borings, development of the sampling and analytical schedule, collection and analyses of groundwater samples, review of analytical and other data, maintenance of the databases containing groundwater monitoring data, quality assurance (QA) evaluations of laboratory performance, and reports of results to waste-site facility custodians and to the Environmental Protection Section (EPS) of EPD.

  7. Modeling the Factors Impacting Pesticide Concentrations in Groundwater Wells

    DEFF Research Database (Denmark)

    Aisopou, Angeliki; Binning, Philip John; Albrechtsen, Hans-Jørgen

    2015-01-01

    variability in the concentration at the well, which helps understanding the results of groundwater monitoring programs. The results are used to provide guidance on the design of pumping and regulatory changes for the long-term supply of safe groundwater. The fate of selected pesticides is examined......, for example, if the application of bentazone in a region with a layered aquifer stops today, the concentration at the well can continue to increase for 20 years if a low pumping rate is applied. This study concludes that because of the rapid response of the pesticide concentration at the drinking water well......This study examines the effect of pumping, hydrogeology, and pesticide characteristics on pesticide concentrations in production wells using a reactive transport model in two conceptual hydrogeologic systems; a layered aquifer with and without a stream present. The pumping rate can significantly...

  8. Groundwater remediation from the past to the future: A bibliometric analysis.

    Science.gov (United States)

    Zhang, Shu; Mao, Guozhu; Crittenden, John; Liu, Xi; Du, Huibin

    2017-08-01

    Groundwater is an important component of terrestrial ecosystems and plays a role in geochemical cycling. Groundwater is also used for agricultural irrigation and for the domestic supply of drinking water in most nations. However, groundwater contamination has led to many research efforts on groundwater remediation technologies and strategies. This study evaluated a total of 5486 groundwater remediation-related publications from 1995 to 2015 using bibliometric technology and social network analysis, to provide a quantitative analysis and a global view on the current research trend and future research directions. Our results underline a strong research interest and an urgent need to remediate groundwater pollution due to the increasing number of both groundwater contamination and remediation publications. In the past two decades, the United States (U.S.) published 41.1% of the papers and it was the core country of the international collaboration network, cooperating with the other 19 most productive countries. Besides the active international collaboration, the funding agencies also played positive roles to foster the science and technology publications. With respect to the analysis of the distribution of funding agencies, the National Science Foundation of China sponsored most of the groundwater remediation research. We also identified the most productive journals, Environmental Science and Technology and Journal of Contaminant Hydrology, which published 334 and 259 scientific articles (including research articles and reviews) over the past 20 years, respectively. In addition to journal publications, a patent analysis was performed to show the impact of intellectual property protection on journal publications. Three major remediation technologies, including chemical oxidation, biodegradation and adsorption, have received increasing interest in both journal publication and patent development. Our results provide a valuable reference and global overview to identify

  9. [Construction of groundwater contamination prevention mapping system].

    Science.gov (United States)

    Wang, Jun-Jie; He, Jiang-Tao; Lu, Yan; Liu, Li-Ya; Zhang, Xiao-Liang

    2012-09-01

    Groundwater contamination prevention mapping is an important component of groundwater contamination geological survey and assessment work, which could provide the basis for making and implementing groundwater contamination prevention planning. A groundwater contamination prevention mapping system was constructed in view of the synthetic consideration on nature perspective derived from groundwater contamination sources and aquifer itself, social-economic perspective, policy perspective derived from outside. During the system construction process, analytic hierarchy process and relevant overlaying principles were used to couple groundwater contamination risk assessment, groundwater value as well as wellhead protection area zoning. Data processing and visualization of mapping results were achieved in the GIS environment. The research on groundwater contamination prevention mapping in Beijing Plain indicated that the final groundwater prevention map was in accordance with the actual conditions and well reflected the priorities of groundwater prevention, which could play a guidance role in designing and implementing further practical prevention and supervision measures. Besides, because of the dynamical properties of the system components, it was suggested to analyze the update frequency of the mapping.

  10. Calendar Year 2016 Annual Groundwater Monitoring Report.

    Energy Technology Data Exchange (ETDEWEB)

    Copland, John R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jackson, Timmie Okchumpulla [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Li, Jun [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Mitchell, Michael Marquand [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Skelly, Michael [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-06-01

    Sandia National Laboratories, New Mexico (SNL/NM) is a government-owned/contractoroperated laboratory. National Technology and Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International, Inc., manages and operates SNL/NM for the U.S. Department of Energy (DOE), National Nuclear Security Administration (NNSA). The DOE/NNSA Sandia Field Office administers the contract and oversees contractor operations at the site. Two types of groundwater surveillance monitoring are conducted at SNL/NM: (1) on a site-wide basis as part of the SNL/NM Long-Term Stewardship (LTS) Program’s Groundwater Monitoring Program (GMP) Groundwater Surveillance Task and (2) on a site-specific groundwater monitoring at LTS/Environmental Restoration (ER) Operations sites with ongoing groundwater investigations. This Annual Groundwater Monitoring Report summarizes data collected during groundwater monitoring events conducted at GMP locations and at the following SNL/NM sites through December 31, 2016: Burn Site Groundwater Area of Concern (AOC); Chemical Waste Landfill; Mixed Waste Landfill; Technical Area-V Groundwater AOC; and the Tijeras Arroyo Groundwater AOC. Environmental monitoring and surveillance programs are required by the New Mexico Environment Department (NMED) and DOE Order 436.1, Departmental Sustainability, and DOE Order 231.1B, Environment, Safety, and Health Reporting.

  11. Alpine Groundwater - Pristine Aquifers Under Threat?

    Science.gov (United States)

    Schneider, P.; Lange, A.

    2014-12-01

    Glacier and permafrost retreat are prominent climate change indicators. However, the characteristics of climate and hydrology in mountain areas remain poorly understood relative to lowland areas. Specifically, not much is known about alpine groundwater, its recharge and water quality variations, as these remote reservoirs are rarely monitored. As global temperatures rise, glaciers and permafrost will continue to retreat forming new sediment deposits and changing infiltration conditions in high alpine terrain. Climate change impacts the hydro-chemical composition of alpine waters, accelerates weathering processes, and potentially triggers mobilization of pollutants. Accordingly, we monitored groundwater quantity and quality parameters of an alpine porous aquifer near the Tiefenbach glacier in the Gotthard Massif in Switzerland. The goal of this research was to assess quality and seasonal storage dynamics of groundwater above the timberline (2000 m). To translate hydrological science into an ecosystem service context, we focused on four attributes: Water quantity: observations of groundwater level fluctuations combined with analysis of contributing water sources based on stable isotope analysis to give a quantitative understanding of origin and amount of water, Water quality: groundwater level, groundwater temperature and electrical conductivity were used as proxies for sampling of hydro-chemical parameters with automated water samplers during primary groundwater recharge periods (snowmelt and rainfall events), Location: Alpine terrain above the timberline, especially recharge into/out of an alpine porous aquifer at a pro-glacial floodplain and Date of annual melt (albedo effect) and timing of flow (snow- and icemelt from May to September) and groundwater recharge during the growing season. The study found that the summer groundwater temperatures depend on the date of annual melt and are more sensitive to climate forcing than lowland groundwater temperatures

  12. Simulating groundwater-induced sewer flooding

    Science.gov (United States)

    Mijic, A.; Mansour, M.; Stanic, M.; Jackson, C. R.

    2016-12-01

    During the last decade, Chalk catchments of southern England experienced severe groundwater flooding. High groundwater levels resulted in the groundwater ingress into the sewer network that led to restricted toilet use and the overflow of diluted, but untreated sewage to road surfaces, rivers and water courses. In response to these events the water and sewerage company Thames Water Utilities Ltd (TWUL) had to allocate significant funds to mitigate the impacts. It was estimated that approximately £19m was spent responding to the extreme wet weather of 2013-14, along with the use of a fleet of over 100 tankers. However, the magnitude of the event was so large that these efforts could not stop the discharge of sewage to the environment. This work presents the analysis of the risk of groundwater-induced sewer flooding within the Chalk catchment of the River Lambourn, Berkshire. A spatially distributed groundwater model was used to assess historic groundwater flood risk and the potential impacts of changes in future climate. We then linked this model to an urban groundwater model to enable us to simulate groundwater-sewer interaction in detail. The modelling setup was used to identify relationships between infiltration into sewers and groundwater levels at specific points on TWUL's sewer network, and to estimate historic and future groundwater flood risk, and how this varies across the catchment. The study showed the significance of understanding the impact of groundwater on the urban water systems, and producing information that can inform a water company's response to groundwater flood risk, their decision making process and their asset management planning. However, the knowledge gained through integrated modelling of groundwater-sewer interactions has highlighted limitations of existing approaches for the simulation of these coupled systems. We conclude this work with number of recommendations about how to improve such hydrological/sewer analysis.

  13. A global-scale two-layer transient groundwater model: Development and application to groundwater depletion

    Science.gov (United States)

    de Graaf, Inge E. M.; van Beek, Rens L. P. H.; Gleeson, Tom; Moosdorf, Nils; Schmitz, Oliver; Sutanudjaja, Edwin H.; Bierkens, Marc F. P.

    2017-04-01

    Groundwater is the world's largest accessible source of freshwater to satisfy human water needs. Moreover, groundwater buffers variable precipitation rates over time, thereby effectively sustaining river flows in times of droughts and evaporation in areas with shallow water tables. In this study, building on previous work, we simulate groundwater head fluctuations and groundwater storage changes in both confined and unconfined aquifer systems using a global-scale high-resolution (5‧) groundwater model by deriving new estimates of the distribution and thickness of confining layers. Inclusion of confined aquifer systems (estimated 6-20% of the total aquifer area) improves estimates of timing and amplitude of groundwater head fluctuations and changes groundwater flow paths and groundwater-surface water interaction rates. Groundwater flow paths within confining layers are shorter than paths in the underlying aquifer, while flows within the confined aquifer can get disconnected from the local drainage system due to the low conductivity of the confining layer. Lateral groundwater flows between basins are significant in the model, especially for areas with (partially) confined aquifers were long flow paths crossing catchment boundaries are simulated, thereby supporting water budgets of neighboring catchments or aquifer systems. The developed two-layer transient groundwater model is used to identify hot-spots of groundwater depletion. Global groundwater depletion is estimated as 7013 km3 (137 km3y-1) over 1960-2010, which is consistent with estimates of previous studies.

  14. Remote instruction in groundwater hydrology

    Science.gov (United States)

    staff of the Interactive Remote Instructional System

    Wright State University (Dayton, Ohio) is preparing for its fourth cycle of the Interactive Remote Instructional System (IRIS) in groundwater hydrology beginning July 15, 1986. The Department of Geological Sciences proudly announces that the first two cycles recorded an impressive 83% completion ratio for registered participants. This completion rate is a significant departure from success rates traditionally recorded by courses of this nature; it is the result of 2 years of implementation and refinement and demonstrates the progressive orientation of the program. The third cycle has been underway since January. This comprehensive hydrogeology program was originally developed for the U.S. Department of Agriculture Soil Conservation Service to prepare their personnel for professional practice work. As a result of that cooperative effort, the IRIS program has evolved to meet the needs of participants by developing a curriculum that reflects current trends in the groundwater industry and has provided a unique educational approach that ensures maximum interaction between the instructional staff and participants.

  15. Groundwater surface mapping informs sources of catchment baseflow

    OpenAIRE

    J. F. Costelloe; T. J. Peterson; K. Halbert; A. W. Western; J. J. McDonnell

    2014-01-01

    Groundwater discharge is a major contributor to stream baseflow. Quantifying this flux is difficult, despite its considerable importance to water resource management and evaluation of the effects of groundwater extraction on streamflow. It is important to be able to differentiate between contributions to streamflow from regional groundwater discharge (more susceptible to groundwater extraction) compared to interflow processes (arguably less susceptible to groundwater ...

  16. Groundwater subsidies and penalties to corn yield

    Science.gov (United States)

    Zipper, S. C.; Booth, E.; Loheide, S. P.

    2013-12-01

    Proper water management is critical to closing yield gaps (observed yield below potential yield) as global populations continue to expand. However, the impacts of shallow groundwater on crop production and surface processes are poorly understood. The presence of groundwater within or just below the root zone has the potential to cause (via oxygen stress in poorly drained soils) or eliminate (via water supply in dry regions) yield gaps. The additional water use by a plant in the presence of shallow groundwater, compared to free drainage conditions, is called the groundwater subsidy; the depth at which the groundwater subsidy is greatest is the optimal depth to groundwater (DTGW). In wet years or under very shallow water table conditions, the groundwater subsidy is likely to be negative due to increased oxygen stress, and can be thought of as a groundwater penalty. Understanding the spatial dynamics of groundwater subsidies/penalties and how they interact with weather is critical to making sustainable agricultural and land-use decisions under a range of potential climates. Here, we examine patterns of groundwater subsidies and penalties in two commercial cornfields in the Yahara River Watershed, an urbanizing agricultural watershed in south-central Wisconsin. Water table levels are generally rising in the region due to a long-term trend of increasing precipitation over the last several decades. Biophysical indicators tracked throughout both the 2012 and 2013 growing seasons show a strong response to variable groundwater levels on a field scale. Sections of the field with optimal DTGW exhibit consistently higher stomatal conductance rates, taller canopies and higher leaf area index, higher ET rates, and higher pollination success rates. Patterns in these biophysical lines of evidence allow us to pinpoint specific periods within the growing season that plants were experiencing either oxygen or water stress. Most importantly, groundwater subsidies and penalties are

  17. Situ treatment of contaminated groundwater

    Energy Technology Data Exchange (ETDEWEB)

    McNab, Jr., Walt W. (Concord, CA); Ruiz, Roberto (Tracy, CA); Pico, Tristan M. (Livermore, CA)

    2001-01-01

    A system for treating dissolved halogenated organic compounds in groundwater that relies upon electrolytically-generated hydrogen to chemically reduce the halogenated compounds in the presence of a suitable catalyst. A direct current is placed across at least a pair, or an array, of electrodes which are housed within groundwater wells so that hydrogen is generated at the cathode and oxygen at the anode. A pump is located within the well housing in which the cathode(s) is(are) located and draws in groundwater where it is hydrogenated via electrolysis, passes through a well-bore treatment unit, and then transported to the anode well(s) for reinjection into the ground. The well-bore treatment involves a permeable cylinder located in the well bore and containing a packed bed of catalyst material that facilitates the reductive dehalogenation of the halogenated organic compounds by hydrogen into environmentally benign species such as ethane and methane. Also, electro-osmatic transport of contaminants toward the cathode also contributes to contaminant mass removal. The only above ground equipment required are the transfer pipes and a direct circuit power supply for the electrodes. The electrode wells in an array may be used in pairs or one anode well may be used with a plurality of cathode wells. The DC current flow between electrode wells may be periodically reversed which controls the formation of mineral deposits in the alkaline cathode well-bore water, as well as to help rejuvenate the catalysis.

  18. Groundwater and climate change: mitigating the global groundwater crisis and adapting to climate change model

    Science.gov (United States)

    To better understand the effects of climate change on global groundwater resources, the United Nations Educational, Scientific, and Cultural Organization (UNESCO) International Hydrological Programme (IHP) initiated the GRAPHIC (Groundwater Resources Assessment under the Pressures of Humanity and Cl...

  19. Leaching of plant protection products and their transformation products : proposals for improving the assessment of leaching to groundwater in the Netherlands : version 2

    NARCIS (Netherlands)

    Boesten, J.J.T.I.; Linden, van der A.M.A.; Beltman, W.H.J.; Pol, J.W.

    2015-01-01

    Assessment of leaching of plant protection products to groundwater is an important aspect of the environmental risk assessment of these substances. Analysis of available Dutch groundwater monitoring data for these substances triggered a critical review of the current Dutch leaching assessment. As a

  20. Monitoring groundwater drought with GRACE data assimilation

    Science.gov (United States)

    Li, B.; Rodell, M.; Beaudoing, H. K.; Getirana, A.; Zaitchik, B. F.

    2015-12-01

    Groundwater drought is a distinct class of drought, not a sub-class of meteorological, agricultural and hydrological drought and has profound impacts on natural environments and societies. Due to a deficiency of in situ measurements, we developed a groundwater drought indicator using groundwater change estimates derived by assimilating GRACE derived terrestrial water storage (TWS) anomalies into the NASA Catchment land surface model. Data assimilation enables spatial and temporal downscaling of coarse GRACE TWS observations (monthly and ~150,000 km2 effective spatial resolution) and extrapolation to near-real time. In this talk, we will present our latest progress on using GRACE satellite data for groundwater drought monitoring in the U.S. and globally. Characteristics of this groundwater drought indicator will be discussed, including its relationship with other types of drought and how they are influenced by model physics and climate conditions. Results are evaluated using in situ groundwater observations.

  1. Quantification of Seepage in Groundwater Dependent Wetlands

    DEFF Research Database (Denmark)

    Johansen, Ole; Beven, Keith; Jensen, Jacob Birk

    2017-01-01

    Restoration and management of groundwater dependent wetlands require tools for quantifying the groundwater seepage process. A method for determining point estimates of the groundwater seepage based on water level observations is tested. The study is based on field data from a Danish rich fen....... Therefore secondly a much simpler mass balance approach is used with lumped descriptions of the most important hydrological processes controlling water level and groundwater inflow to the system. The water level dynamics are here described and bracketed nicely and a dynamic description of the seepage rate...... the dynamic description of groundwater seepage can be very useful in future studies of the links between seepage, soil water chemistry and vegetation in groundwater dependent terrestrial ecosystems....

  2. ARSENIC CONTAMINATION IN GROUNDWATER: A STATISTICAL MODELING

    Directory of Open Access Journals (Sweden)

    Palas Roy

    2013-01-01

    Full Text Available High arsenic in natural groundwater in most of the tubewells of the Purbasthali- Block II area of Burdwan district (W.B, India has recently been focused as a serious environmental concern. This paper is intending to illustrate the statistical modeling of the arsenic contaminated groundwater to identify the interrelation of that arsenic contain with other participating groundwater parameters so that the arsenic contamination level can easily be predicted by analyzing only such parameters. Multivariate data analysis was done with the collected groundwater samples from the 132 tubewells of this contaminated region shows that three variable parameters are significantly related with the arsenic. Based on these relationships, a multiple linear regression model has been developed that estimated the arsenic contamination by measuring such three predictor parameters of the groundwater variables in the contaminated aquifer. This model could also be a suggestive tool while designing the arsenic removal scheme for any affected groundwater.

  3. Inter-relationship between shallow and deep aquifers under the influence of deep groundwater exploitation in the North China Plain

    Science.gov (United States)

    Han, Dongmei; Cao, Guoliang; Love, Andrew J.

    2017-04-01

    In the North China Plain (NCP), the interaction between shallow and deep groundwater flow systems enhanced by groundwater extraction has been investigated using multi-isotopic and chemical tracers for understanding the mechanism of salt water transport, which has long been one of the major regional environmental hydrogeological problems in NCP. Information about the problem will be determined using multiple lines of evidence, including field surveys of drilling and water sampling, as well as laboratory experiments and physical and numerical simulations. A conceptual model of groundwater flow system along WE cross-section from piedmont area to coastal region (Shijiazhuang-Hengshui-Cangzhou) has been developed and verified by geochemical modeling. A combined hydrogeochemical and isotopic investigation using ion relationships such as Cl/Br ratios, and environment isotopes (δ 18O, δ 2H, δ 34SSO4-δ 18OSO4, δ 15NNO_3-δ 18ONO_3, δ 13C and 87Sr/86Sr) was reviewed and carried for determining the sources of aquifer recharge, the origin of solutes and the mixing processes in groundwater flow system under the anthropogenic pumping and pollution. Results indicate that hydrochemistry of groundwater is characterized by mixing between end-members coming directly from Piedmont recharge areas, saline groundwater formed during geohistorical transgression in the shallow aquifers of central plain, and to groundwater circulating in a deeply buried Quaternary sediments. We also reviewed the groundwater age (tritium contents, 14C ages, 3H-3He ages, basin-scale flow modeling ages of groundwater) to recognize the local distributed recharge in this strongly exploited aquifer system. Finally, combined with the 1-D Cl transport modeling for the pore water of clay-rich aquitard, we reveal that salt transport in the aquitard is primarily controlled by vertical diffusion on million years' time scale, and the observed the salinized groundwater in deep aquifer may be caused by passing

  4. Groundwater-dependent ecosystems: recent insights, new techniques and an ecosystem-scale threshold response

    Directory of Open Access Journals (Sweden)

    D. Eamus

    2015-05-01

    Full Text Available Groundwater-dependent ecosystems (GDEs are at risk globally due to unsustainable levels of groundwater extraction, especially in arid and semi-arid regions. In this review, we examine recent developments in the ecohydrology of GDEs with a focus on three knowledge gaps: (1 how do we locate GDEs, (2 how much water is transpired from shallow aquifers by GDEs; and (3 what are the responses of GDEs to excessive groundwater extraction? The answers to these questions will determine water allocations that are required to sustain functioning of GDEs and to guide regulations on groundwater extraction to avoid negative impacts on GDEs. We discuss three methods for identifying GDEs: (1 fluctuations in depth-to-groundwater that are associated with diurnal variations in transpiration, (2 stable isotope analysis of water sources in the transpiration stream; and (3 remote sensing methods. We then discuss several methods for estimating rates of GW use, including direct measurement using sapflux or eddy covariance technologies, estimation of a climate wetness index within a Budyko framework, spatial distribution of ET using remote sensing, groundwater modelling and stable isotopes. Remote sensing methods often rely on direct measurements to calibrate the relationship between vegetation indices and ET. ET from GDEs is also determined using hydrologic models of varying complexity, from the "White method" to fully coupled, variable saturation models. Combinations of methods are typically employed to obtain clearer insight into the components of groundwater discharge in GDEs, such as the proportional importance of transpiration vs. evaporation (e.g., using stable isotopes or from groundwater vs. rainwater sources. Groundwater extraction can have severe consequences on structure and function of GDEs. In the most extreme cases, phreatophytes experience crown dieback and death following groundwater drawdown. We provide a brief review of two case studies of the impacts

  5. LITERATURE SURVEY FOR GROUNDWATER TREATMENT OPTIONS FOR NITRATE IODINE-129 AND URANIUM 200-ZP-1 OPERABLE UNIT HANFORD SITE

    Energy Technology Data Exchange (ETDEWEB)

    BYRNES ME

    2008-06-05

    This literature review presents treatment options for nitrate, iodine-129, and uranium, which are present in groundwater at the 200-ZP-I Groundwater Operable Unit (OU) within the 200 West Area of the Hanford Site. The objective of this review is to determine available methods to treat or sequester these contaminants in place (i.e., in situ) or to pump-and-treat the groundwater aboveground (i.e., ex situ). This review has been conducted with emphasis on commercially available or field-tested technologies, but theoretical studies have, in some cases, been considered when no published field data exist. The initial scope of this literature review included only nitrate and iodine-I 29, but it was later expanded to include uranium. The focus of the literature review was weighted toward researching methods for treatment of nitrate and iodine-129 over uranium because of the relatively greater impact of those compounds identified at the 200-ZP-I OU.

  6. Compendium of ordinances for groundwater protection

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    Groundwater is an extremely important resource in the Tennessee Valley. Nearly two-thirds of the Tennessee Valley's residents rely, at least in part, on groundwater supplies for drinking water. In rural areas, approximately ninety-five percent of residents rely on groundwater for domestic supplies. Population growth and economic development increase the volume and kinds of wastes requiring disposal which can lead to groundwater contamination. In addition to disposal which can lead to groundwater contamination. In addition to disposal problems associated with increases in conventional wastewater and solid waste, technological advancements in recent decades have resulted in new chemicals and increased usage in agriculture, industry, and the home. Unfortunately, there has not been comparable progress in identifying the potential long-term effects of these chemicals, in managing them to prevent contamination of groundwater, or in developing treatment technologies for removing them from water once contamination has occurred. The challenge facing residence of the Tennessee Valley is to manage growth and economic and technological development in ways that will avoid polluting the groundwater resource. Once groundwater has been contaminated, cleanup is almost always very costly and is sometimes impractical or technically infeasible. Therefore, prevention of contamination -- not remedial treatment--is the key to continued availability of usable groundwater. This document discusses regulations to aid in this prevention.

  7. Groundwater Level Predictions Using Artificial Neural Networks

    Institute of Scientific and Technical Information of China (English)

    毛晓敏; 尚松浩; 刘翔

    2002-01-01

    The prediction of groundwater level is important for the use and management of groundwater resources. In this paper, the artificial neural networks (ANN) were used to predict groundwater level in the Dawu Aquifer of Zibo in Eastern China. The first step was an auto-correlation analysis of the groundwater level which showed that the monthly groundwater level was time dependent. An auto-regression type ANN (ARANN) model and a regression-auto-regression type ANN (RARANN) model using back-propagation algorithm were then used to predict the groundwater level. Monthly data from June 1988 to May 1998 was used for the network training and testing. The results show that the RARANN model is more reliable than the ARANN model, especially in the testing period, which indicates that the RARANN model can describe the relationship between the groundwater fluctuation and main factors that currently influence the groundwater level. The results suggest that the model is suitable for predicting groundwater level fluctuations in this area for similar conditions in the future.

  8. The challenges facing sustainable and adaptive groundwater ...

    African Journals Online (AJOL)

    The challenges facing sustainable and adaptive groundwater management ... provide the capacity to assure effective and sustainable resource regulation and allocation. ... of alternative strategies needed to achieve sustainable management.

  9. Estimating Groundwater Development area in Jianan Plain using Standardized Groundwater Index

    Science.gov (United States)

    Yu, Chang Hsiang; Haw, Lee Cheng

    2017-04-01

    Taiwan has been facing severe water crises in recent years owing to the effects of extreme weather conditions. Changes in precipitation patterns have also made the drought phenomenon increasingly prominent, which has indirectly affected groundwater recharge. Hence, in the present study, long-term monitoring data were collected from the study area of the Jianan plain. The standardized groundwater index (SGI) and was then used to analyse the region's drought characteristics. To analyse the groundwater level by using SGI, making SGI180 groundwater level be the medium water crises, and SGI360 groundwater level be the extreme water crises. Through the different water crises signal in SGI180 and SGI360, we divide groundwater in Jianan plain into two sections. Thereby the water crises indicators establishing groundwater level standard line in Jianan Plain, then using the groundwater level standard line to find the study area where could be groundwater development area in Jianan plain. Taking into account relatively more water scarcity in dry season, so the study screen out another emergency backup groundwater development area, but the long-term groundwater development area is still as a priority development area. After finding suitable locations, groundwater modeling systems(GMS) software is used to simulate our sites to evaluate development volume. Finally, the result of study will help the government to grasp the water shortage situation immediately and solve the problem of water resources deployment.

  10. Groundwater potentiality mapping of hard-rock terrain in arid regions using geospatial modelling: example from Wadi Feiran basin, South Sinai, Egypt

    Science.gov (United States)

    Arnous, Mohamed O.

    2016-09-01

    Identifying a good site for groundwater exploitation in hard-rock terrains is a challenging task. In Sinai, Egypt, groundwater is the only source of water for local inhabitants. Interpretation of satellite data for delineation of lithological units and weathered zones, and for mapping of lineament density and their trends, provides a valuable aid for the location of groundwater promising areas. Complex deformational histories of the wide range of lithological formations add to the difficulty. Groundwater prospect mapping is a systematic approach that considers the major controlling factors which influence the aquifer and quality of groundwater. The presented study aims to delineate, identify, model and map groundwater potential zones in arid South Sinai using remote sensing data and a geographic information system (GIS) to prepare various hydromorphogeological thematic maps such as maps of slope, drainage density, lithology, landforms, structural lineaments, rainfall intensity and plan curvature. The controlling-factor thematic maps are each allocated a fixed score and weight, computed by using a linear equation approach. Furthermore, each weighted thematic map is statistically computed to yield a groundwater potential zone map of the study area. The groundwater potential zones thus obtained were divided into five categories (very poor, poor, moderate, good and very good) and were validated using the relation between the zone and the spatial distribution of productive wells and of previous geophysical investigations from a literature review. The results show the groundwater potential zones in the study area, and create awareness for better planning and management of groundwater resources.

  11. Unbalance on power systems: a general review

    Energy Technology Data Exchange (ETDEWEB)

    Reineri, Claudio A.; Gomez Targarona, Juan C.

    2009-07-01

    A general revision of different aspects in relation to the voltage unbalance in electric power systems is presented, that should necessarily be deeply known by technical operators and designers of facilities, installations, and electric equipment. Dissimilar unbalance definitions, unbalance measurement methods, their quantification and the interpretation of such magnitudes are revised. The causes of the unbalances in electric power systems were described and analyzed. The effects on power systems are also studied, specially those that have influence on: system operability, lost of efficiency of the three phase system and their impact in the definitions of traditional power. Similarly is studied the unbalance effect on certain loads, in particular: three-phase motors, power electronics and ASD's. Also methods to locate the origin of these problems, as well as the different normative or standards, and possible methods to mitigate their effects are deeply detailed. It is concluded in the necessity to deepen the study of the power system unbalance, because numerous non resolved aspects still exist whose solution requires of a deep knowledge on the part of the involved professionals. (author)

  12. Virtual smile design systems: a current review.

    Science.gov (United States)

    Zimmermann, Moritz; Mehl, Albert

    2015-01-01

    In the age of digital dentistry, virtual treatment planning is becoming an increasingly important element of dental practice. Thanks to new technological advances in the computer- assisted design and computer-assisted manufacturing (CAD/CAM) of dental restorations, predictable interdisciplinary treatment using the backward planning approach appears useful and feasible. Today, a virtual smile design can be used as the basis for creating an esthetic virtual setup of the desired final result. The virtual setup, in turn, is used to plan further treatment steps in an interdisciplinary team approach, and communicate the results to the patient. The smile design concept and the esthetic analyses required for it are described in this article. We include not only a step-by-step description of the virtual smile design workflow, but also describe and compare the several available smile design options and systems. Subsequently, a brief discussion of the advantages and limitations of virtual smile design is followed by a section on different ways to integrate a two-dimensional (2D) smile design into the digital three-dimensional (3D) workflow. New technological developments are also described, such as the integration of smile designs in digital face scans, and 3D diagnostic follow-up using intraoral scanners.

  13. TRANSCUTANEOUS DRUG DELIVERY SYSTEM: A COMPREHENSIVE REVIEW

    Directory of Open Access Journals (Sweden)

    Sandhu Premjeet

    2011-12-01

    Full Text Available Conventional drug delivery systems are often not suitable for new protein based and other Therapeutic compounds produced by modern technology. Therefore an alternative Approach to deliver these drugs can be achieved through the skin in the form of transcutaneous drug delivery system. Modern medicine has responded with the development of methods to deliver drug transcutanously (through the skin for therapeutic use as an alternative to traditional route including oral, intravascular, intramuscular, subcutaneous, and sublingual. Transcutaneous drug delivery has many theoretic and practical advantage and disadvantages, and such issues are often a concern for both clinicians and patients. Transcutaneous patches are flexible pharmaceutical preparations of varying sizes, containing one or more active ingredient, intended to be applied to the unbroken skin in order to deliver the active ingredient to the systemic circulation after passing through the skin barriers. A Transcutaneous patch or skin patch is a medicated adhesive patch that is placed on the skin to deliver a specific dose of medication through the skin and into the bloodstream. Often, this promotes healing to an injured area of the body. In this method, the drug enters the bloodstream directly through skin and it avoid first pass effect. Characterization of Transcutaneous patch are necessary because check it’s quality, size, time of onset & duration, adhesive property, thickness, weight of patch, moisture of content, uniformity & cutaneous toxicological studies. Their requirements for evaluation are HPLC, U.V. spectrophotometer, screw gauge, digital balance, desiccators, thin layer chromatography & K.C. Cell used.

  14. Current dental adhesives systems. A narrative review.

    Science.gov (United States)

    Milia, Egle; Cumbo, Enzo; Cardoso, Rielson Jose A; Gallina, Giuseppe

    2012-01-01

    Adhesive dentistry is based on the development of materials which establish an effective bond with the tooth tissues. In this context, adhesive systems have attracted considerable research interest in recent years. Successful adhesive bonding depends on the chemistry of the adhesive, on appropriate clinical handling of the material as well as on the knowledge of the morphological changes caused on dental tissue by different bonding procedures. This paper outlines the status of contemporary adhesive systems, with particular emphasis on chemical characteristics and mode of interaction of the adhesives with enamel and dentinal tissues. Dental adhesives are used for several clinical applications and they can be classified based on the clinical regimen in "etch-and-rinse adhesives" and "self-etch adhesives". Other important considerations concern the different anatomical characteristics of enamel and dentine which are involved in the bonding procedures that have also implications for the technique used as well as for the quality of the bond. Etch-and-rinse adhesive systems generally perform better on enamel than self-etching systems which may be more suitable for bonding to dentine. In order to avoid a possible loss of the restoration, secondary caries or pulp damage due to bacteria penetration or due to cytotoxicity effects of eluted adhesive components, careful consideration of several factors is essential in selecting the suitable bonding procedure and adhesive system for the individual patient situation.

  15. On "enabling systems - A strategic review"

    Digital Repository Service at National Institute of Oceanography (India)

    Nayak, M.R.

    and infrastructural elements to place IT as an enabling technology to meet the challenges ahead. The Plan only covers issues related to the deployment of IT in a research organizational context. However, it excludes issues relating to the teaching of IT and IT...

  16. The Diego blood group system: a review.

    Science.gov (United States)

    Figueroa, Dolores

    2013-01-01

    The Diego blood group system (DI) currently encompasses 22 antigens. Three of the antigens are of high prevalence and the other 19 are of low prevalence. The antigens of the Diego blood group system are carried on the erythroid band 3 protein anion exchanger 1 (AE1), the product of a single gene, SLC4A1 (solute carrier family 4, anion exchanger, member 1). AE1 is a member of a family of three anion exchangers or transporters expressed in a variety of tissues. This protein is involved in carbon dioxide transport from tissues to lungs. It is also found in the kidney,where it is involved in acid secretion. Antibodies to Diego system antigens with the exception of anti-Dia, -Dib, -Wra, -ELO and-DISK do not seem to be of clinical significance for transfusion or of importance in hemolytic disease of the fetus and newborn.

  17. Groundwater management for agriculture and nature: an economic analysis

    NARCIS (Netherlands)

    Hellegers, P.J.G.J.

    2001-01-01

    Key words: desiccation of nature, economics of water management, groundwater extraction, groundwater level management, ecohydrology, agriculture, policy instruments.

    As a result of declining groundwater levels, nature in the Netherlands is suffering

  18. Groundwater Management for Agriculture and Nature : an Economic Analysis

    NARCIS (Netherlands)

    Hellegers, P.

    2001-01-01

    Key words: desiccation of nature, economics of water management, groundwater extraction, groundwater level management, ecohydrology, agriculture, policy instruments.As a result of declining groundwater levels, nature in the Netherlands is suffering from desiccation. Since measures taken to raise gro

  19. Mathematical description of adsorption and transport of reactive solutes in soil: a review of selected literature. [Theory is applicable in such diverse areas as agriculture, nuclear waste management, sanitary engineering, and groundwater hydrology

    Energy Technology Data Exchange (ETDEWEB)

    Travis, C.C.

    1978-10-01

    This report reviews selected literature related to the mathematical description of the transport of reactive solutes through soil. The primary areas of the literature reviewed are (1) mathematical models in current use for description of the adsorption-desorption interaction between the soil solution and the soil matrix and (2) analytic solutions of the differential equations describing the convective-dispersive transport of reactive solutes through soil.

  20. Investigation of geochemical indicators to evaluate the connection between inland and coastal groundwater systems near Kaloko-Honokōhau National Historical Park, Hawai‘i

    Science.gov (United States)

    Tillman, Fred D; Oki, Delwyn S.; Johnson, Adam G.; Barber, Larry B.; Beisner, Kimberly R.

    2014-01-01

    Kaloko-Honokōhau National Historical Park (KAHO) is a coastal sanctuary on the western side of the Island of Hawai‘i that was established in 1978 to preserve, interpret, and perpetuate traditional Native Hawaiian culture and activities. KAHO contains a variety of culturally and ecologically significant water resources and water-related habitat for species that have been declared as threatened or endangered by the U.S. Fish and Wildlife Service, or are candidate threatened or endangered species. These habitats are dependent on coastal unconfined groundwater in a freshwater-lens system. The coastal unconfined-groundwater system is recharged by local infiltration of rainfall but also may receive recharge from an inland groundwater system containing groundwater impounded to high altitudes. The area inland of and near KAHO is being rapidly urbanized and increased groundwater withdrawals from the inland impounded-groundwater system may affect habitat and water quality in KAHO, depending on the extent of connection between the coastal unconfined groundwater and inland impounded-groundwater. An investigation of the geochemistry of surface-water and groundwater samples in and near KAHO was performed to evaluate the presence or absence of a connection between the inland impounded- and coastal unconfined-groundwater systems in the area. Analyses of major ions, selected trace elements, rare-earth elements, and strontium-isotope ratio results from ocean, fishpond, anchialine pool, and groundwater samples were consistent with a linear mixing process between the inland impounded and coastal unconfined-groundwater systems. Stable isotopes of water in many samples from the coastal unconfined-groundwater system require an aggregate recharge altitude that is substantially higher than the boundary between the coastal unconfined and inland impounded systems, a further indication of a hydrologic connection between the two systems. The stable isotope composition of the freshwater

  1. Changes in projected spatial and seasonal groundwater recharge in the upper Colorado River Basin

    Science.gov (United States)

    Tillman, Fred; Gangopadhyay, Subhrendu; Pruitt, Tom

    2017-01-01

    The Colorado River is an important source of water in the western United States, supplying the needs of more than 38 million people in the United States and Mexico. Groundwater discharge to streams has been shown to be a critical component of streamflow in the Upper Colorado River Basin (UCRB), particularly during low-flow periods. Understanding impacts on groundwater in the basin from projected climate change will assist water managers in the region in planning for potential changes in the river and groundwater system. A previous study on changes in basin-wide groundwater recharge in the UCRB under projected climate change found substantial increases in temperature, moderate increases in precipitation, and mostly periods of stable or slight increases in simulated groundwater recharge through 2099. This study quantifies projected spatial and seasonal changes in groundwater recharge within the UCRB from recent historical (1950 to 2015) through future (2016 to 2099) time periods, using a distributed-parameter groundwater recharge model with downscaled climate data from 97 Coupled Model Intercomparison Project Phase 5 (CMIP5) climate projections. Simulation results indicate that projected increases in basin-wide recharge of up to 15% are not distributed uniformly within the basin or throughout the year. Northernmost subregions within the UCRB are projected an increase in groundwater recharge, while recharge in other mainly southern subregions will decline. Seasonal changes in recharge also are projected within the UCRB, with decreases of 50% or more in summer months and increases of 50% or more in winter months for all subregions, and increases of 10% or more in spring months for many subregions.

  2. Review on penetration of barriers by contaminants and technologies for groundwater and soil contamination control%污染物击穿防污屏障与地下水土污染防控研究进展

    Institute of Scientific and Technical Information of China (English)

    陈云敏; 谢海建; 张春华

    2016-01-01

    Barrier systems are the most important structures for landfills in terms of groundwater pollution control. Analytical solutions to one-dimensional models of transport of heavy metals and organic contaminants in clay barriers and composite barriers were summarized in order to evaluate the service life of the barrier systems. The analytical solutions include the solution to a one-dimensional model of diffusion of contaminants in clay barriers under piecewise linear adsorption conditions, the solution to a one-dimensional model of transport of contaminants in composite barriers with geomembrane defects, and the solution to a coupled model of transport of pollutants in clay barriers under thermal effects. The reliability of high-gravity centrifuge tests of long-term transport of contaminants through barriers was assessed. Field investigation was carried out in a 17-year old landfill in Anhui Province. The results showed that the maximum migration depth of chloride ion reached 9 m, and the maximum migration depth of sodium ions and COD reached 3 to 4 m. The technologies of vertical barriers for control of groundwater and soil contamination were summarized and assessed. It was found that the application of soil-bentonite cutoff walls in China generates prosperity, and further research areas were discussed.%鉴于防污屏障是控制固废填埋场地下水土污染的重要结构,为评价防污屏障的服役寿命,分别针对重金属和有机污染物,总结了污染物在黏土屏障和复合屏障中的一维运移解析解,包括非线性吸附条件下污染物在黏土屏障中的一维扩散解、污染物在有缺陷膜复合屏障中的一维运移解和温度场作用下污染物在黏土屏障中的耦合运移解析解等。评价了污染物击穿防污屏障长历时过程超重力离心模型试验的可靠性。对运行了17 a的安徽某填埋场进行现场调查,发现氯离子运移最大深度达9 m,钠离子和COD的运移深度在3~4 m。总

  3. The Present Situation and Countermeasures of Groundwater Contamination in Japan

    OpenAIRE

    Shindo, Shizuo; Tang, Changyuan

    1997-01-01

    [ABSTRACT] Since 1982, thousands of groundwater pollution cases have been found in Japan. In order to improve the groundwater quality, Japan has developed strategies for protection of groundwater. In this paper, authors try to explain the present of groundwater use, groundwater pollution and remediation methods in Japan. From the results shown in this paper, it can be found that groundwater pollution problem has become very serious in Japan. Even many efforts have been made to improve the sit...

  4. Evaluation of Groundwater Pollution Nitrogen Fertilizer Using Expert System

    OpenAIRE

    Ta-oun, Mongkon; Daud, Mohamed; Bardaie, Mohd Zohadie

    2017-01-01

    An expert system was used to correlate the availability of nitrogen fertilizer with the vulnerability of groundwater to pollution in Peninsula Malaysia to identify potential groundwater quality problems. The expert system could predict the groundwater pollution potential under several conditions of agricultural activities and exiting environments. Four categories of groundwater pollution potential were identified base on an N-fertilizer groundwater pollution potential index. A groundwater pol...

  5. Assessing Groundwater Depletion and Dynamics Using GRACE and InSAR: Potential and Limitations.

    Science.gov (United States)

    Castellazzi, Pascal; Martel, Richard; Galloway, Devin L; Longuevergne, Laurent; Rivera, Alfonso

    2016-11-01

    In the last decade, remote sensing of the temporal variation of ground level and gravity has improved our understanding of groundwater dynamics and storage. Mass changes are measured by GRACE (Gravity Recovery and Climate Experiment) satellites, whereas ground deformation is measured by processing synthetic aperture radar satellites data using the InSAR (Interferometry of Synthetic Aperture Radar) techniques. Both methods are complementary and offer different sensitivities to aquifer system processes. GRACE is sensitive to mass changes over large spatial scales (more than 100,000 km(2) ). As such, it fails in providing groundwater storage change estimates at local or regional scales relevant to most aquifer systems, and at which most groundwater management schemes are applied. However, InSAR measures ground displacement due to aquifer response to fluid-pressure changes. InSAR applications to groundwater depletion assessments are limited to aquifer systems susceptible to measurable deformation. Furthermore, the inversion of InSAR-derived displacement maps into volume of depleted groundwater storage (both reversible and largely irreversible) is confounded by vertical and horizontal variability of sediment compressibility. During the last decade, both techniques have shown increasing interest in the scientific community to complement available in situ observations where they are insufficient. In this review, we present the theoretical and conceptual bases of each method, and present idealized scenarios to highlight the potential benefits and challenges of combining these techniques to remotely assess groundwater storage changes and other aspects of the dynamics of aquifer systems.

  6. Determination of ecologically vital groundwaters at selected sites in the Formerly Utilized Sites Remedial Action Program

    Energy Technology Data Exchange (ETDEWEB)

    Vinikour, W.S.; Yin, S.C.L.

    1989-08-01

    The US Department of Energy is classifying groundwaters at sites in its Formerly Utilized Sites Remedial Action Program (FUSRAP). Of particular concern is the potential presence of groundwaters that are highly vulnerable to contamination and that are either (1) irreplaceable sources of drinking water or (2) ecologically vital. Conditions at nine FUSRAP sites were evaluated to determine if ecologically vital groundwaters are present. The sites evaluated were Wayne Interim Storage Site, Maywood Interim Storage Site, and Middlesex Sampling Plant in New Jersey; Ashland 2 Site, Seaway Industrial Park, Colonie Interim storage Site, and Niagara Falls Storage Site in New York; and the St. Louis Airport Site and Hazelwood Interim Storage Site in Missouri. The analyses indicated that groundwaters are vulnerable to contamination at all but two of the sites -- the Ashland 2 and Seaway Industrial Park sites in New York. Groundwater discharge points were identified within a 2-mile radius (i.e., the classification review area) of all of the sites. No ecologically vital groundwater areas exist in the vicinities of any of the nine FUSRAP sites evaluated. 35 refs., 17 figs.

  7. Assessing groundwater depletion and dynamics using GRACE and InSAR: Potential and limitations

    Science.gov (United States)

    Castellazzi, Pascal; Martel, Richard; Galloway, Devin L.; Longuevergne, Laurent; Rivera, Alfonso

    2016-01-01

    In the last decade, remote sensing of the temporal variation of ground level and gravity has improved our understanding of groundwater dynamics and storage. Mass changes are measured by GRACE (Gravity Recovery and Climate Experiment) satellites, whereas ground deformation is measured by processing synthetic aperture radar satellites data using the InSAR (Interferometry of Synthetic Aperture Radar) techniques. Both methods are complementary and offer different sensitivities to aquifer system processes. GRACE is sensitive to mass changes over large spatial scales (more than 100,000 km2). As such, it fails in providing groundwater storage change estimates at local or regional scales relevant to most aquifer systems, and at which most groundwater management schemes are applied. However, InSAR measures ground displacement due to aquifer response to fluid-pressure changes. InSAR applications to groundwater depletion assessments are limited to aquifer systems susceptible to measurable deformation. Furthermore, the inversion of InSAR-derived displacement maps into volume of depleted groundwater storage (both reversible and largely irreversible) is confounded by vertical and horizontal variability of sediment compressibility. During the last decade, both techniques have shown increasing interest in the scientific community to complement available in situ observations where they are insufficient. In this review, we present the theoretical and conceptual bases of each method, and present idealized scenarios to highlight the potential benefits and challenges of combining these techniques to remotely assess groundwater storage changes and other aspects of the dynamics of aquifer systems.

  8. Antarctic subglacial groundwater: measurement concept and potential influence on ice flow

    Science.gov (United States)

    Kulessa, Bernd; Siegert, Martin; Bougamont, Marion; Christoffersen, Poul; Key, Kerry; Andersen, Kristoffer; Booth, Adam; Smith, Andrew

    2017-04-01

    Is groundwater abundant in Antarctica and does it modulate ice flow? Answering this question matters because ice streams flow by gliding over a wet substrate of till. Water fed to ice-stream beds thus influences ice-sheet dynamics and, potentially, sea-level rise. It is recognised that both till and the sedimentary basins from which it originates are porous and could host a reservoir of mobile groundwater that interacts with the subglacial interfacial system. According to recent numerical modelling up to half of all water available for basal lubrication, and time lags between hydrological forcing and ice-sheet response as long as millennia, may have been overlooked in models of ice flow. Here, we review evidence in support of Antarctic groundwater and propose how it can be measured to ascertain the extent to which it modulates ice flow. We present new seismoelectric soundings of subglacial till, and new magnetotelluric and transient electromagnetic forward models of subglacial groundwater reservoirs. We demonstrate that multi-facetted and integrated geophysical datasets can detect, delineate and quantify the groundwater contents of subglacial sedimentary basins and, potentially, monitor groundwater exchange rates between subglacial till layers. We thus describe a new area of glaciological investigation and how it should progress in future.

  9. Response of the microbial community to seasonal groundwater level fluctuations in petroleum hydrocarbon-contaminated groundwater.

    Science.gov (United States)

    Zhou, Ai-xia; Zhang, Yu-ling; Dong, Tian-zi; Lin, Xue-yu; Su, Xiao-si

    2015-07-01

    The effects of seasonal groundwater level fluctuations on the contamination characteristics of total petroleum hydrocarbons (TPH) in soils, groundwater, and the microbial community were investigated at a typical petrochemical site in northern China. The measurements of groundwater and soil at different depths showed that significant TPH residue was present in the soil in this study area, especially in the vicinity of the pollution source, where TPH concentrations were up to 2600 mg kg(-1). The TPH concentration in the groundwater fluctuated seasonally, and the maximum variation was 0.8 mg L(-1). The highest TPH concentrations were detected in the silty clay layer and lied in the groundwater level fluctuation zones. The groundwater could reach previously contaminated areas in the soil, leading to higher groundwater TPH concentrations as TPH leaches into the groundwater. The coincident variation of the electron acceptors and TPH concentration with groundwater-table fluctuations affected the microbial communities in groundwater. The microbial community structure was significantly different between the wet and dry seasons. The canonical correspondence analysis (CCA) results showed that in the wet season, TPH, NO3(-), Fe(2+), TMn, S(2-), and HCO3(-) were the major factors correlating the microbial community. A significant increase in abundance of operational taxonomic unit J1 (97% similar to Dechloromonas aromatica sp.) was also observed in wet season conditions, indicating an intense denitrifying activity in the wet season environment. In the dry season, due to weak groundwater level fluctuations and low temperature of groundwater, the microbial activity was weak. But iron and sulfate-reducing were also detected in dry season at this site. As a whole, groundwater-table fluctuations would affect the distribution, transport, and biodegradation of the contaminants. These results may be valuable for the control and remediation of soil and groundwater pollution at this site

  10. Global Climate Responses to Anthropogenic Groundwater Exploitation

    Science.gov (United States)

    Zeng, Y.; Xie, Z.

    2015-12-01

    In this study, a groundwater exploitation scheme is incorporated into the earth system model, Community Earth System Model 1.2.0 (CESM1.2.0), which is called CESM1.2_GW, and the climatic responses to anthropogenic groundwater withdrawal are then investigated on global scale. The scheme models anthropogenic groundwater exploitation and consumption, which are then divided into agricultural irrigation, industrial use and domestic use. A group of 41-year ensemble groundwater exploitation simulations with six different initial conditions, and a group of ensemble control simulations without exploitation are conducted using the developed model CESM1.2_GW with water supplies and demands estimated. The results reveal that the groundwater exploitation and water consumption cause drying effects on soil moisture in deep layers and wetting effects in upper layers, along with a rapidly declining groundwater table in Central US, Haihe River Basin in China and Northern India and Pakistan where groundwater extraction are most severe in the world. The atmosphere also responds to anthropogenic groundwater exploitation. Cooling effects on lower troposphere appear in large areas of North China Plain and of Northern India and Pakistan. Increased precipitation occurs in Haihe River Basin due to increased evapotranspiration from irrigation. Decreased precipitation occurs in Northern India because water vapor here is taken away by monsoon anomalies induced by anthropogenic alteration of groundwater. The local reducing effects of anthropogenic groundwater exploitation on total terrestrial water storage evinces that water resource is unsustainable with the current high exploitation rate. Therefore, a balance between slow groundwater withdrawal and rapid human economic development must be achieved to maintain a sustainable water resource, especially in over-exploitation regions such as Central US, Northern China, India and Pakistan.

  11. Ecology and living conditions of groundwater fauna

    Energy Technology Data Exchange (ETDEWEB)

    Thulin, Barbara (Geo Innova AB (Sweden)); Hahn, Hans Juergen (Arbeitsgruppe Grundwasseroekologie, Univ. of Koblenz-Landau (Germany))

    2008-09-15

    This report presents the current state of ecological knowledge and applied research relating to groundwater. A conceptual picture is given of groundwater fauna occurrence in regard to Swedish environmental conditions. Interpretation features for groundwater fauna and applications are outlined. Groundwater is one of the largest and oldest limnic habitats populated by a rich and diverse fauna. Both very old species and species occurring naturally in brackish or salt water can be found in groundwater. Groundwater ecosystems are heterotrophic; the fauna depends on imports from the surface. Most species are meiofauna, 0.3-1 mm. The food chain of groundwater fauna is the same as for relatives in surface water and salt water. Smaller animals graze biofilms and detritus, larger animals act facutatively as predators. A difference is that stygobiotic fauna has become highly adapted to its living space and tolerates very long periods without food. Oxygen is a limiting factor, but groundwater fauna tolerates periods with low oxygen concentrations, even anoxic conditions. For longer periods of time a minimum oxygen requirement of 1 mg/l should be fulfilled. Geographic features such as Quaternary glaciation and very old Pliocene river systems are important for distribution patterns on a large spatial scale, but aquifer characteristics are important on a landscape scale. Area diversity is often comparable to surface water diversity. However, site diversity is low in groundwater. Site specific hydrological exchange on a geological facies level inside the aquifer, e.g. porous, fractured and karstic aquifers as well as the hyporheic zone, controls distribution patterns of groundwater fauna. For a better understanding of controlling factors indicator values are suggested. Different adequate sampling methods are available. They are representative for the aquifer, but a suitable number of monitoring wells is required. The existence of groundwater fauna in Sweden is considered as very

  12. Brackish groundwater in the United States

    Science.gov (United States)

    Stanton, Jennifer S.; Anning, David W.; Brown, Craig J.; Moore, Richard B.; McGuire, Virginia L.; Qi, Sharon L.; Harris, Alta C.; Dennehy, Kevin F.; McMahon, Peter B.; Degnan, James R.; Böhlke, John Karl

    2017-04-05

    For some parts of the Nation, large-scale development of groundwater has caused decreases in the amount of groundwater that is present in aquifer storage and that discharges to surface-water bodies. Water supply in some areas, particularly in arid and semiarid regions, is not adequate to meet demand, and severe drought is affecting large parts of the United States. Future water demand is projected to heighten the current stress on groundwater resources. This combination of factors has led to concerns about the availability of freshwater to meet domestic, agricultural, industrial, mining, and environmental needs. To ensure the water security of the Nation, currently [2016] untapped water sources may need to be developed.Brackish groundwater is an unconventional water source that may offer a partial solution to current and future water demands. In support of the national census of water resources, the U.S. Geological Survey completed the national brackish groundwater assessment to better understand the occurrence and characteristics of brackish groundwater in the United States as a potential water resource. Analyses completed as part of this assessment relied on previously collected data from multiple sources; no new data were collected. Compiled data included readily available information about groundwater chemistry, horizontal and vertical extents and hydrogeologic characteristics of principal aquifers (regionally extensive aquifers or aquifer systems that have the potential to be used as a source of potable water), and groundwater use. Although these data were obtained from a wide variety of sources, the compiled data are biased toward shallow and fresh groundwater resources; data representing groundwater that is at great depths and is saline were not as readily available.One of the most important contributions of this assessment is the creation of a database containing chemical characteristics and aquifer information for the known areas with brackish groundwater

  13. Considering groundwater use to improve the assessment of groundwater pumping for irrigation in North Africa

    Science.gov (United States)

    Massuel, Sylvain; Amichi, Farida; Ameur, Fatah; Calvez, Roger; Jenhaoui, Zakia; Bouarfa, Sami; Kuper, Marcel; Habaieb, Hamadi; Hartani, Tarik; Hammani, Ali

    2017-04-01

    Groundwater resources in semi-arid areas and especially in the Mediterranean face a growing demand for irrigated agriculture and, to a lesser extent, for domestic uses. Consequently, groundwater reserves are affected and water-table drops are widely observed. This leads to strong constraints on groundwater access for farmers, while managers worry about the future evolution of the water resources. A common problem for building proper groundwater management plans is the difficulty in assessing individual groundwater withdrawals at regional scale. Predicting future trends of these groundwater withdrawals is even more challenging. The basic question is how to assess the water budget variables and their evolution when they are deeply linked to human activities, themselves driven by countless factors (access to natural resources, public policies, market, etc.). This study provides some possible answers by focusing on the assessment of groundwater withdrawals for irrigated agriculture at three sites in North Africa (Morocco, Tunisia and Algeria). Efforts were made to understand the different features that influence irrigation practices, and an adaptive user-oriented methodology was used to monitor groundwater withdrawals. For each site, different key factors affecting the regional groundwater abstraction and its past evolution were identified by involving farmers' knowledge. Factors such as farmer access to land and groundwater or development of public infrastructures (electrical distribution network) are crucial to decode the results of well inventories and assess the regional groundwater abstraction and its future trend. This leads one to look with caution at the number of wells cited in the literature, which could be oversimplified.

  14. Considering groundwater use to improve the assessment of groundwater pumping for irrigation in North Africa

    Science.gov (United States)

    Massuel, Sylvain; Amichi, Farida; Ameur, Fatah; Calvez, Roger; Jenhaoui, Zakia; Bouarfa, Sami; Kuper, Marcel; Habaieb, Hamadi; Hartani, Tarik; Hammani, Ali

    2017-09-01

    Groundwater resources in semi-arid areas and especially in the Mediterranean face a growing demand for irrigated agriculture and, to a lesser extent, for domestic uses. Consequently, groundwater reserves are affected and water-table drops are widely observed. This leads to strong constraints on groundwater access for farmers, while managers worry about the future evolution of the water resources. A common problem for building proper groundwater management plans is the difficulty in assessing individual groundwater withdrawals at regional scale. Predicting future trends of these groundwater withdrawals is even more challenging. The basic question is how to assess the water budget variables and their evolution when they are deeply linked to human activities, themselves driven by countless factors (access to natural resources, public policies, market, etc.). This study provides some possible answers by focusing on the assessment of groundwater withdrawals for irrigated agriculture at three sites in North Africa (Morocco, Tunisia and Algeria). Efforts were made to understand the different features that influence irrigation practices, and an adaptive user-oriented methodology was used to monitor groundwater withdrawals. For each site, different key factors affecting the regional groundwater abstraction and its past evolution were identified by involving farmers' knowledge. Factors such as farmer access to land and groundwater or development of public infrastructures (electrical distribution network) are crucial to decode the results of well inventories and assess the regional groundwater abstraction and its future trend. This leads one to look with caution at the number of wells cited in the literature, which could be oversimplified.

  15. Ground-water contribution to dose from past Hanford Operations

    Energy Technology Data Exchange (ETDEWEB)

    Freshley, M.D.; Thorne, P.D.

    1992-08-01

    The Hanford Environmental Dose Reconstruction (HEDR) Project is being conducted to estimate radiation doses that populations and individuals could have received from Hanford Site operations from 1944 to the present. Four possible pathways by which radionuclides migrating in ground water on the Hanford Site could have reached the public have been identified: (1) through contaminated ground water migrating to the Columbia River; (2) through wells on or adjacent to the Hanford Site; (3) through wells next to the Columbia River downstream of Hanford that draw some or all of their water from the river (riparian wells); and (4) through atmospheric deposition resulting in contamination of a small watershed that, in turn, results in contamination of a shallow well or spring by transport in the ground water. These four pathways make up the ground-water pathway,'' which is the subject of this study. Assessment of the ground-water pathway was performed by (1) reviewing the existing extensive literature on ground water and ground-water monitoring at Hanford and (2) performing calculations to estimate radionuclide concentrations where no monitoring data were collected. Radiation doses that would result from exposure to these radionuclides were calculated.

  16. Radioactive Seepage through Groundwater Flow from the Uranium Mines, Namibia

    Directory of Open Access Journals (Sweden)

    Tamiru Abiye

    2017-02-01

    Full Text Available The study focused on the seepage of uranium from unlined tailing dams into the alluvial aquifer in the Gawib River floodplain in Namibia where the region solely relies on groundwater for its economic activities as a result of arid climatic condition. The study reviewed previous works besides water sample collection and analyses for major ions, metals and environmental isotopes in addition to field tests on physico-chemical parameters (pH, Electrical Conductivity, Redox and T. Estimation of seepage velocity (true velocity of groundwater flow has been conducted in order to understand the extent of radioactive plume transport. The hydrochemistry, stable isotopes and tritium results show that there is uranium contamination from the unlined uranium tailings in the Gawib shallow aquifer system which suggests high permeability of the alluvial aquifer facilitating groundwater flow in the arid region. The radioactive contaminants could spread into the deeper aquifer system through the major structures such as joints and faults. The contamination plume could also spread downstream into the Swakop River unless serious interventions are employed. There is also a very high risk of the plume to reach the Atlantic Ocean through seasonal flash floods that occurs in the area.

  17. Regulating groundwater use in developing countries

    DEFF Research Database (Denmark)

    Hansen, Lars Gårn; Jensen, Frank; Amundsen, Eirik S

    2014-01-01

    Worldwide groundwater is a common-pool resource that is potentially subject to the tragedy of the commons if water extraction is not adequately regulated. In developing countries the regulatory infrastructure is often too weak to allow detailed monitoring of individual groundwater extraction. For...

  18. Groundwater use on southern Idaho dairies

    Science.gov (United States)

    Dairy production has expanded in irrigated areas of the western and southwestern US, potentially competing for limited water supplies. Groundwater withdrawal was measured for two years on six dairy farms with 660 to 6400 milk cows in southern Idaho. Groundwater withdrawal was calculated on an equiva...

  19. Applied groundwater modeling, 2nd Edition

    Science.gov (United States)

    Anderson, Mary P.; Woessner, William W.; Hunt, Randall J.

    2015-01-01

    This second edition is extensively revised throughout with expanded discussion of modeling fundamentals and coverage of advances in model calibration and uncertainty analysis that are revolutionizing the science of groundwater modeling. The text is intended for undergraduate and graduate level courses in applied groundwater modeling and as a comprehensive reference for environmental consultants and scientists/engineers in industry and governmental agencies.

  20. Propagation of drought through groundwater systems

    NARCIS (Netherlands)

    Peters, E.

    2003-01-01

    Index words: drought, groundwater, simulation, synthetic data, extreme events

    The transformation of droughts as a result of the propagation through groundwater systems is examined by comparing droughts in time